Like many of his countrymen in professional sumo, Hakuhō belongs to a family in the Mongolian wrestling tradition. His father Jigjidiin Mönkhbat won a silver medal in freestyle wrestling at the 1968 Summer Olympics, his country's first ever Olympic medal, and held the highest ranking in Mongolian wrestling, "Darkhan Avarga" (meaning "Invincible Champion"), which is the Mongolian equivalent of yokozuna. Davaajargal did not however have any formal training in Mongolian wrestling himself, as his father wished him to try other sports, and he concentrated on basketball as a child instead. However, at an early age he would be seen reading sumo magazines, and when his father asked him why he liked sumo so much, he responded by saying he wanted to be as big as a sumo wrestler one day. At that time he was considered below average in size.
He came to Japan in October 2000 when he was fifteen years old, invited by pioneering Mongolian wrestler Kyokushūzan. Because he weighed only 62 kg (137 lb), no sumo training stable (heya) was prepared to accept him. Hearing this, Kyokushūzan asked heya master Miyagino-oyakata to intercede, and Davaajargal was accepted to Miyagino stable on the last day of his two-month stay in Japan, 24 December 2000. He was given the ring name (shikona) Hakuhō, with haku meaning "white" and hō, meaning the Chinese mythological bird Peng. His shikona also emulates that of former yokozuna Taihō.
Hakuhō made his professional debut at the March tournament (honbasho) in Osaka in 2001. Despite having no previous wrestling experience, as his weight increased he steadily rose in the ranks, reaching the second highest jūryō division in January 2004, and the top makuuchi division in May of the same year. In his very first top-division tournament, he scored twelve wins against three losses and was awarded a special prize (sanshō) for Fighting Spirit. He also enjoyed great success in subsequent tournaments, winning a gold star (kinboshi) for defeating yokozuna Asashōryū in November 2004 while still at the lowest makuuchi rank of maegashira. This tournament also saw him finish as runner-up for the first time. He achieved a rapid promotion to the rank of komusubi in January 2005 and sekiwake only one tournament later. His progress was delayed by an injury which forced him to take leave (zen-kyu) from the Nagoya tournament in 2005.
His ōzeki promotion came in March 2006 after a 13-2 record, which included a playoff for the championship (which he lost to Asashōryū) and also earned him two special prizes for Outstanding Performance and Technique. This gave him a three tournament record of 35 wins against ten losses. His promotion was confirmed just a few weeks after his twenty-first birthday, making him the fourth youngest wrestler to reach ōzeki in modern sumo history.
At his first tournament as ōzeki in May 2006, with Asashōryū absent, Hakuhō won his first championship (yūshō) with a 14-1 record, defeating Miyabiyama in another playoff. After another strong performance (13-2) in July, in which he finished as runner-up to Asashōryū and defeated him on the final day, Hakuhō flirted with promotion to yokozuna, but an uncharacteristically poor 8-7 showing in September shelved such early hopes. An injury sustained in training prevented him from participating in the November tournament, putting him at risk for demotion (kadoban) in January 2007, when he scored a respectable ten wins on his return to the ring.
In March 2007 Hakuhō won his second championship in Osaka and a third championship in the very next tournament in May, with a perfect 15-0 record. Winning two consecutive championships satisfies the de facto minimum requirements for promotion to the top rank in sumo. On the day following the tournament, the Yokozuna Deliberation Council unanimously recommended his promotion to yokozuna which was formally announced by the Japan Sumo Association on 30 May 2007. He performed his inaugural ring-entering ceremony (dohyō-iri) at the Meiji Shrine (in the lesser-used Shiranui style) on 1 June. He performed the ceremony at the Kokugikan during Kyokushūzan's retirement ceremony (danpatsu-shiki) on 2 June.
Hakuhō's first tournament as a yokozuna was in July 2007. His 25 match winning streak was brought to an end by Kotomitsuki on the 10th day, and further losses to Kotoōshū and Chiyotaikai put him out of contention for the title. He finished the tournament with an 11-4 record.
Hakuhō's first tournament championship as a yokozuna came in September 2007 with a 13-2 record, triumphing over Chiyotaikai on the last day. His second title as a yokozuna, and fifth overall, came in the following tournament in November with a 12-3 score. He lost to Kotomitsuki on the final day but the championship had already been decided earlier in the day when his only challenger Chiyotaikai pulled out through injury. His yokozuna rival Asashōryū missed both these tournaments through suspension.
In the January 2008 tournament, he faced the returning Asashōryū on the final day with both wrestlers having a 13-1 score. In a bout lasting nearly a minute, Hakuhō defeated Asashōryū, winning his 6th championship with a 14-1 record. In the March 2008 tournament the two yokozuna met once again to decide the title and this time Asashōryū got his revenge, with Hakuhō finishing as runner-up.
In the May 2008 tournament, he won his first nine consecutive bouts. On the 10th day, however, he lost to Ama for the fourth time in their last five meetings, injuring his ankle in the process. Subsequent losses to Kotoōshū (the eventual winner of the tournament) and Kotomitsuki put him out of contention for the championship. He finished on 11-4, losing to Asashōryū on the final day in a match that sparked scandal after the two yokozuna nearly came to blows when Asashōryū gave Hakuhō an extra shove after the bout was over. Both wrestlers were given a warning over their conduct by the Japan Sumo Association.
In July 2008, with Asashōryū pulling out through injury he won his seventh championship without a serious challenge, securing victory by the 13th day: the first time this had been achieved since January 2005. He finished the tournament unbeaten; his second zenshō-yūshō. Although he lost on day five of the September tournament, he still dominated all other opponents and secured another championship on the 14th day. He finished the tournament with a 14-1 record.
In the November tournament Hakuhō was once again the sole yokozuna participating. He lost his opening bout to Aminishiki and his 12th day bout to Ama. Both Hakuhō and Ama finished with a 13-2 record and the eventual play-off was won by Hakuhō, handing him his fourth yūshō of the season and ninth in total.
In the January 2009 tournament Hakuhō defeated Asashōryū on the final day in their first meeting since May, handing his fellow yokozuna his first defeat of the tournament and leaving both men with identical 14-1 records. Hakuhō was however beaten in the subsequent playoff. Hakuhō defeated Asashōryū again in the March tournament, this time capping off an undefeated 15-0 championship, his third zenshō-yūshō and his tenth championship overall.
In May he extending his winning run to 33 regulation bouts, the best since Asashōryū's 35 in 2004, until he was defeated by Kotoōshū on Day 14. He recovered to beat Asashōryū on Day 15 to finish at 14-1, but he lost the playoff bout to Harumafuji who claimed his first championship.
In July he won his eleventh championship, finishing one win ahead of Kotoōshū with another 14-1 score. He almost pulled off his twelfth championship in the following September tournament. One win behind Asashōryū for most of the tournament after giving away his first kinboshi in a year (to Shōtenrō) he forced a playoff by beating his rival on the final day, but then lost in the succeeding playoff bout. This was a very similar scenario to his loss to Asashōryū in the preceding January tournament. Regardless of this loss, he still managed to become the first makuuchi wrestler ever to win fourteen or more bouts in five consecutive tournaments. He also became the first wrestler ever to lose three makuuchi playoffs in one year. After the tournament he was diagnosed with ligament damage in his left elbow; however surgery was not required.
On 28 November, the fourteenth day of the Kyushu basho, he clinched his twelfth tournament championship and broke Asashōryū's 2005 record for most bouts won in a calendar year, which had stood at 84. He defeated Asashōryū the following day to secure his fourth career zenshō-yūshō and set his 2009 record total at 86 wins. This was also his fourteenth consecutive yūshō or jun-yūshō (winner or runner-up) performance, another record.
In the opening tournament of the year Hakuhō's 30 bout winning streak was ended by Baruto on Day 7, and he suffered consecutive losses to ozeki Harumafuji and Kaiō on Days 12 and 13 to concede the title to Asashōryū by Day 14. He gained some consolation by beating his yokozuna rival for the seventh straight time in regulation bouts on the final day to finish the tournament on 12-3.
Hakuhō expressed his shock at the retirement of Asashōryū in February, following allegations his fellow yokozuna had assaulted a man in a drunken brawl outside a nightclub during the previous tournament. Fighting back tears he said, "I don't want to believe it. I was honoured to wrestle in the same era as him." After getting regularly beaten by Asashōryū earlier in his career, Hakuhō came to completely dominate him, winning all of their last seven regulation matches (excluding two tournament-playoff defeats) and finishing with a 14-13 record over his greatest rival.
He won the Osaka tournament in March with a perfect 15-0 record, his fifth undefeated score and thirteenth championship overall. After his victory he spoke of the extra pressure now that he was sumo's lone yokozuna and his relief at the win.
Hakuhō wrapped up his fourteenth championship in May by Day 13 (his earliest yūshō win since July 2008) and went on to record his sixth zenshō-yūshō, the first time he has achieved this in consecutive tournaments. With the win, he equalled the number of yūshō won by yokozuna Wajima, and to commemorate this he switched to wearing Wajima's trademark gold coloured mawashi.
In July 2010 a special committee reviewing the extent of illegal gambling within sumo revealed that Hakuhō had bet several tens of thousands of yen on hanafuda Japanese card games with his fellow wrestlers twice a year or so. However, the committee said that he would not be punished as it was not considered a serious offence. He nonetheless appeared along with nearly 80 other wrestlers at a press conference and apologised to sumo fans for his actions. On the 14th day of the Nagoya tournament he won his 46th consecutive bout, surpassing Taihō's 45, behind only Chiyonofuji's 53 and Futabayama's 69 as the longest winning run since the beginning of the Showa era. He clinched his fifteenth yūshō on the same day, and on the final day he secured his third consecutive 15-0 record, the first wrestler ever to achieve this. However, he did not receive the Emperor's Cup or any other trophy, as the Sumo Association decided to withdraw them in response to the gambling scandal. Hakuhō commented, "I hope we will not have a tournament like this ever again."
On Day 6 of the Aki basho in September he equalled the 53-bout winning streak of Chiyonofuji with a win over Kotoshōgiku, and surpassed it the following day by pushing out Kisenosato in front of the first sell-out crowd of the tournament so far. He said afterwards that he felt "I really repaid my debt of gratitude" to the former Chiyonofuji. He secured his fourth consecutive yūshō on the fourteenth day when rank-and-filers Yoshikaze and Takekaze suffered defeats, and he moved to 14-0 (and 61 consecutive wins) by beating Kotoōshū. Asked about Futabayama's record of 69 wins, set in the two tournament a year era from 1936 to 1939, he responded, "It is truly amazing that he was able to continue winning for almost three years." Former Sumo Association Kitanoumi estimated that Hakuhō had a possibility of "about 80 percent" of breaking the record, which he would achieve on the eighth day of the November tournament. Hakuhō wrapped up the Aki basho by defeating Harumafuji to achieve his fourth perfect record in a row. This was also his eighth zenshō-yūshō overall, equalling the record held jointly Futabayama and Taihō.
On the first day of the November 2010 tournament, Hakuhō defeated Tochinoshin, tying the consecutive wins record of Tanikaze with 63. However, on the following day his run was finally brought to an end when he was defeated by Kisenosato. This was only the fifth time in his yokozuna career that Hakuhō has been defeated by a maegashira, and Kisenosato is the first to earn more than one kinboshi from him, having previously upset him in September 2008. However, Hakuhō won all his remaining bouts and defeated maegashira Toyonoshima in a playoff to win the championship. He finished the year on 86 wins in regulation matches, equalling the record he set in 2009. At a press conference following his victory, he revealed that having his winning run halted before breaking Futabayama's record affected him so badly that he considered withdrawing from the tournament.
On 21 December he was awarded the Japan Professional Sports Grand Prize, receiving the Prime Minister's Trophy from Naoto Kan.
In the January 2011 tournament in Tokyo he was surprisingly beaten by Kisenosato for the second time in a row but he secured his eighteenth championship on the fourteenth day. In doing so Hakuhō became only the third man after Taihō and Asashōryū to win six consecutive tournaments.
During the May "technical examination tournament" Hakuhō notched up his 500th win in the top division, with a victory over Kitataiki on Day 5. He achieved this total with the loss of just 99 top division bouts since his debut in May 2004 – a winning percentage of 83%. He was defeated by Harumafuji on Day 13 but went on to win his seventh straight championship, equalling Asashōryū's record, despite losing to Kaiō on the final day.
Hakuhō was defeated on the eleventh day of the July 2011 tournament by sekiwake Kotoshōgiku and his quest for a record eighth straight yūshō ended on Day 14 when he was beaten by Harumafuji to drop two wins behind. He also lost his final day match to Baruto to finish on 12-3, his poorest result since January 2010. Nevertheless, it was still enough for runner-up honours, his twelfth.
He was defeated by Kisenosato for the third time in five meetings on Day 12 of the September tournament and then lost to Kotoshōgiku for the second time in a row the following day. However he rallied to beat Baruto on Day 14 and then Harumafuji on the final day to clinch his twentieth tournament championship. On 25 November 2011, he won his 21st tournament title in Fukuoka, moving to 13-0 with none of his rivals scoring better than 10-3. He finished the tournament on 14-1, his only loss coming to Baruto on the final day.
Hakuhō finished second to Baruto in the opening tournament of 2012, losing to Kakuryū, Harumafuji and Kotoōshū. He did however maintain his record of finishing runner-up or better in his last 26 tournaments. In the March basho, Hakuhō won his twenty-second yūshō after beating Kakuryū in a playoff, finishing with a 13-2 record. Hakuhō's only losses came to Kakuryū on the 9th day and Kisenosato on the 13th day. Kakuryū had entered the final day of the tournament one match ahead of the yokozuna but lost to Gōeidō, and Hakuhō beat Baruto to force a playoff. This marked the first time a wrestler had come from one win behind to claim the yūshō on the final day since Asashōryū defeated Hokutōriki in a playoff in May 2004. With this victory Hakuhō drew level with Takanohana in fifth place on the all–time list of most top division tournament championships.
In the May 2012 tournament Hakuhō fractured his left index finger in an opening day loss to Aminishiki, and he dropped further matches to Toyohibiki, Gōeidō and Toyonoshima on Days 7, 8 and 9 to stand at only 5–4 after nine days. However he then won five bouts in a row and was even in with an outside chance of claiming the yūshō until it was announced that Kotoōshū was withdrawing on the final day and giving Tochiōzan an automatic twelfth win. Hakuhō's defeat by Harumafuji on Day 15 meant he finished on 10–5, his worst ever score as a yokozuna and the first time since his debut at the rank, 29 tournaments ago, that he failed to be at least the runner–up.
After losing to Harumafuji on the last day in both the July and September tournaments (as well as maegashira Tochiōzan in September) and seeing his fellow Mongolian claim the yūshō in both and earn promotion to yokozuna himself, Hakuhō came back to win his 23rd championship in November, losing only to Kotoōshū on Day 11. He also finished as the wrestler with the most wins in the calendar year for the sixth consecutive time, a record. His victory was also his sixth straight Kyushu tournament triumph, the best run since Chiyonofuji′s record eight in a row from 1981 to 1988.
Hakuhō finished joint runner up on 12–3 in the opening tournament of 2013, giving up a kinboshi to Myōgiryū on Day 3 and also losing to Kotoōshū and Harumafuji. However he captured his 24th title in the Haru basho in March, remaining undefeated for the whole fifteen days. This was his first zenshō-yūshō since his record winning streak of 2010 and also the ninth of his career, breaking the all-time record he had shared with Taihō and Futabayama. It also drew him level with Kitanoumi in fourth place on the list of most career championships, behind only Asashōryū with 25, Chiyonofuji with 31 and Taihō with 32. Hakuhō also recorded his 650th win in the top division in this tournament, moving him into eighth place all-time. In the May tournament he won his 25th championship, equaling Asashōryū's mark. By again recording an undefeated tournament record, his final two victories coming over Kisenosato and Harumafuji, he increased his winning streak to 30 bouts.
Hakuhō extended his streak to 43 bouts by winning his first 13 matches in the Nagoya tournament in July, before he was finally defeated by Kisenosato on Day 14. He also lost to Harumafuji on the final day, but both these defeats came after his 26th tournament victory had already been assured. He won his fourth tournament in a row, and the 27th of his career, in the Aki basho in September, losing only one bout to Gōeidō. In November he went into a final day showdown with his fellow yokozuna Harumafuji, with both men tied on 13-1. Harumafuji won this bout to claim his sixth championship, with Hakuhō having to settle for his 17th second-place result. He finished the year with 82 wins out of 90 bouts, a record that has only been bettered by himself (twice) and Asashōryū.
Hakuhō won the first tournament of 2014. After going undefeated in his first 14 matches, Hakuhō lost to Kakuryū on the final day. As Kakuryū had a 14-1 record, this prompted the two to again meet in a tie-breaking bout. After losing 20 minutes prior, Hakuhō won his twenty-eighth yūshō by defeating Kakuryū in this tie breaker.
In the March tournament, Hakuhō was bested by Kakuryū and finished runner-up, tied with Gōeidō at 12-3. He returned in May to win his twenty-ninth yūshō with a record of 14-1, only losing once to Gōeidō. He then won his thirtieth yūshō with a 13-2 record in July, becoming only the third man in history to have 30 or more top division championships.
On Day 14 of the September tournament, he defeated the up-and-coming Ichinojō, who he was tied with at 12-1. The following day, Hakuhō clinched the championship, winning his third tournament in a row, and the 31st of his career, having lost only one bout, to Gōeidō. It also drew him level with Chiyonofuji in second place on the list of most career championships.
In the next tournament in Fukuoka, he continued his dominance, again losing only one bout (against Takayasu on day six) and taking the championship to tie him with Taihō for the most championships in sumo history, defeating fellow yokozuna Kakuryū with a yorikiri push-out, for a 14-1 record and his 32nd Emperor's Cup. Hakuhō finally was able to fulfill a promise he had made during a visit to Taihō just two days before his death in January 2013 and equal the record, which had stood for over 40 years. After an emotional presentation ceremony Hakuhō remarked, “I could achieve this accomplishment because the soul of the Japanese and the god of sumo gave a mandate to my efforts.”
Hakuhō broke Taihō's record in the opening tournament of 2015, clinching the championship on the 13th day by defeating Kisenosato and maintaining a perfect score into the final days. Hakuhō finished the tournament with a perfect score of 15-0 while all contenders had at least four losses. Sumo Association chairman Kitanoumi commented, "Nobody can touch Hakuho... I’d like to see him go for 40 titles. If he keeps going the way he is, that’s a possibility." He was however criticized for turning up an hour late to his press conference the next day, having reportedly been out drinking until 7am celebrating his victory.
In Osaka in March Hakuhō won his sixth consecutive championship, a feat only achieved four times previously (twice by Taihō, once by Asashōryū and once by himself). His 36 bout winning streak was brought to an end by Terunofuji on Day 13, but he won all his other matches to finish one ahead of Terunofuji on 14-1. During this tournament he also overtook Chiyonofuji to move into second place on the all-time list of most wins in the top division, behind only Kaiō. In May he lost on the opening day of a tournament for the first time in three years, to Ichinojo. He ended up finishing runner-up to Terunofuji on 11-4, thus ending his hopes of equalling his and Asashōryū's record of seven straight championships. However, he won his 35th title in Nagoya in July, finishing two wins ahead of the rest of the field on 14-1.
In September Hakuhō lost to Okinoumi and Yoshikaze on the first two days and then announced that he would miss the rest of the tournament owing to an injury which was diagnosed as tendinitis in the left quadriceps. After withdrawing from a tournament for the first time since 2006 Hakuhō said "I couldn’t get any power.. I apologize to everyone. I can’t step into the ring with half-hearted feelings". His withdrawal brought to an end his run of 722 consecutive matchdays competing as a yokozuna and 51 consecutive tournaments with a score of 10-5 or better, both records. On his return in November he appeared to be in dominant form and won his first twelve matches, but defeats in the last three days to Harumafuji, Terunofuji and Kakuryū saw him end the tournament in a three-way tie for second place. His most unusual win came on day 10 when he used the rarely-seen nekodamashi ("cat trick") technique to defeat Tochiōzan.
In January 2016 Hakuhō won his first ten matches but then lost to Kotoshōgiku, the eventual winner of the tournament, on Day 11. He also lost his last two bouts to Kisenosato and Harumafuji to end with a 12-3 record and a tie for second place. This result meant he had gone three tournaments without winning the championship for the first time since 2012. In March he lost to Takarafuji on the first day but won his remaining fourteen matches to take his 36th championship. His win was poorly received as he employed a henka (sidestep at the initial charge) to defeat Harumafuji on the final day and clinch the title. Speaking after the match Hakuhō said he never planned to win with a henka "and I feel really bad about that."
On the opening day of the May tournament in Tokyo he equalled Kaiō's record of 879 top division wins, and surpassed it the next day by gaining revenge over Takarafuji who had defeated him in the previous tournament. He secured his 37th championship on the fourteenth day when his only challenger Kisenosato fell to his second loss, and he rounded off the tournament by defeating Kakuryū with a rare backward pivot throw (utchari) to ensure a 29th consecutive victory and a perfect 15–0 record. His winning streak of 33 bouts was brought to an end on the 5th day of the July 2016 tournament when he lost once again to Takarafuji. He finished the tournament with a mediocre 10–5 record, hampered by an injury to his right big toe. He struggled to recover from his injuries and on 8 September he announced that he would miss the whole of the upcoming tournament explaining "I’m sorry to the fans. I want work on healing in time for the autumn regional tour and the Kyushu Basho".
After undergoing surgery on his toe injury Hakuhō returned to action at the November tournament. On the third day he became only the third wrestler, after Chiyonofuji and Kaiō, to reach 1000 career wins. Afterwards he admitted to nerves having fallen short of his target with a 10–5 record in July and then having to sit out the September tournament, and expressed relief that he was "finally able to do it." Hakuhō went on to get a 11-4 record in November. For the first time in ten years Hakuhō didn't get the most wins in a calendar year, only getting 62 wins. Instead Kisenosato won the most victories in the year getting 69 wins. This is primarily due to Hakuhō pulling out for the entire September tournament. Additionally Hakuhō only managed to win two tournaments in 2016 the least since 2012 where he also only won two.
In the opening tournament of 2017 Hakuhō lost on Day 8 to maegashira Arawashi (a rare example of him losing to a wrestler he had never fought before) and komusubi Takayasu on Day 9. After being defeated on the last two days by Takanoiwa and tournament winner Kisenosato, he finished in a share for third place. This marks the first time in Hakuhō's yokozuna career that he has gone four tournaments without winning the championship.
Hakuhō has a straightforward but effective style, reminiscent of yokozuna Takanohana. He has been called the "quintessential all-round sumo wrestler" because of his strength in both grappling and pushing techniques, and his ability to read and respond to his opponent's intentions. However, he has said he does not have a special or favourite kimarite, and that "the only thing I am very good at is yorikiri (force-out)". This technique, the most common kimarite in sumo, is used by Hakuhō to win 28% of his matches. He favours the migi-yotsu position, meaning his right hand is inside and his left hand is outside his opponent's arms, and he has become famous for his left hand outside grip. He also regularly employs uwate-nage, or outer-arm throw. While meeting foreign journalists in April 2009 Hakuhō said he was studying the techniques of the 35th yokozuna Futabayama, a wrestler whom he greatly admires, in particular his approach to the tachi-ai or initial charge. In 2016 Kotoshōgiku remarked, "Hakuho has so many weapons, like his fleetness of foot and how he puts you off balance."
Hakuhō has been criticized for giving his opponents an unnecessary final shove after the bout was already over (dameoshi). He did this on Day 4 of the March 2016 tournament in his win over Okinoumi and again on Day 8, when he sent Yoshikaze crashing into the ring side judge Izutzu Oyakata, fracturing Izutzu's left femur and putting him out of action for three months. Hakuhō was warned by the head of the judging committee, Isegahama Oyakata, who said, "he has to understand completely that (such) redundant finishing blows are dangerous." Hakuhō apologized, calling his actions "inexcusable... Even I have weaknesses in the ring that I want to correct." Speaking after his tournament victory in May 2016 he commented, "I don’t know why but when I get into the ring, I turn into a different Hakuho. I think there are two Hakuhos. I'm gentler when I'm not in the ring."
In February 2007 Hakuhō married Sayoko Wada, then 22 years old, a university student and glamour model, after a three-year relationship. The wedding ceremony took place at Meiji Shrine. The couple has a daughter, born in May 2007, a son, born in September 2008, and a daughter, born in January 2011.