Arnold's daughter, Elissa, is the partner of Australia national football team defender Trent Sainsbury. Arnold Place in the Sydney suburb of Glenwood is named for him.
Arnold was a striker who started his career at Gwawley Bay in 1969. He played for them until 1979 when he moved to Canterbury-Marrickville in the New South Wales Premier League. He then moved to Sydney Croatia in Australia's now defunct National Soccer League, where he was both the league's top goal scorer and player of the year in 1986. This was followed by a move overseas, where he made a name for himself in the Netherlands, playing for Roda JC and NAC Breda. He also spent time in Belgium with R.F.C. de Liège and R. Charleroi S.C.. He went on to play for Sanfrecce Hiroshima in Japan towards the end of his career, before finally returning home to play for the Northern Spirit FC.
Graham Arnold has represented Australia's senior national team 54 times, scoring 19 goals (85 caps, 33 goals including unofficial matches and "B" internationals). He was given his full debut by Frank Arok in a World Cup Qualifier against Taiwan at Adelaide's Hindmarsh Stadium on 23 October 1985. He scored on his debut as the "Socceroos" went on to record a 7–0 victory. His international playing career came to a sad end on 29 November 1997 in a World Cup Qualifier against Iran at the MCG when the score ended 2–2 and Australia was eliminated on the away goals rule after leading 2–0.
Arnold had a cameo role as a coach very early on in his career. He was coach for 2 games whilst he was a player at Sydney Croatia during the 1989/90 season. However, his proper coaching career started in 1998, when he was appointed player/manager of the Northern Spirit FC. He was the coach for 2 seasons, making the playoffs in their debut season.
He was then appointed to the position of Australian assistant coach in 2000, becoming acting coach in July 2006, then appointed head coach in December 2006.
On 6 September 2006 Australia was defeated 2–0 in an Asian Cup qualifying game against lowly-ranked Kuwait. The FFA confirmed Arnold would remain Head Coach through to the end of 2007 Asian Cup campaign.
Australia started their Asian Cup campaign poorly, drawing with Oman in its opening Group stage game in Bangkok. Media pressure focused on Arnold and on 13 July 2007 Australia were beaten 3–1 by Iraq in the 2007 Asian Cup. Following the match, Arnold told the assembled media (in reference to some of the team's higher profile members), "There's some players who seem like they don't want to be here. I'm extremely disappointed."
In a poll conducted by Four Four Two, Graham Arnold, as voted by the subscribers, was found to have been the most influential reason for Australia's failed progression at the 2006 Asian Cup, with an overwhelming 78% of the vote
Since the tournament, Arnold has continued his role as Manager of the Australian U-23 side that is in the final qualification stages for the 2008 Olympics. He was also linked with the manager's position at Bolton Wanderers and Norwich City in England but lost out to Gary Megson and Glenn Roeder respectively.
With the appointment of Dutchman Pim Verbeek as the Australian manager, Arnold along with Henk Duut served as his assistant to the national side during the 2010 FIFA World Cup in South Africa.
On 9 February 2010, it was announced that Arnold will take on the position of head coach for the Central Coast Mariners until the end of the 2012/2013 season. At the conclusion of the 2011–12 A-League season he rejected a lucrative contract from Sydney FC and decided to stay on with the Mariners signing a one-year extension to his original contract with the club.
In the month of November 2013 Graham was a target for a few clubs in Asia, especially Vegalta Sendai in Japan's J1 League. Although interest again raised from the Australian Football Federation to make Graham the national team coach, he always wanted to stay in club football over the national team setup and within weeks agreed terms with Sendai to be the first Australian coach, since the late Eddie Thomson to coach at the highest level in Japanese football. Graham recruited his assistant from the Central Coast Mariners Andrew Clark to join him in Japan. On 9 April 2014, it was announced by Vegalta Sendai that Arnold had been sacked. Arnold came to the media later in the day, to set the record straight that his leaving was a mutual agreement and he hadn't been sacked as originally reported. His departure from the club came after a winless 8-game streak endured by Sendai in the league and cup competitions.
Arnold was appointed as the new head coach of Sydney FC on 8 May 2014. In his first season with the Sky Blues, they were runners-up in the 2014–15 A-League season, finishing second behind Melbourne Victory, and losing the 2015 A-League Grand Final to them.
After their fairly respectable 2014-15 season, they saw an unsuccessful 2015-16 A-League season, finish in 7th place and missing out on the Finals Series. He was, however, able to lead the team to a top place finish in Group H for their 2016 AFC Champions League campaign. They were eventually knocked out by Chinese team Shandong Luneng 3-3 on aggregate in the Round of 16.
To prevent another nightmare campaign, Arnold started his revamp of the squad by releasing 13 players in the pre-season. To solve the teams goalscoring issues, he bought in Brazilian striker Bobô as their new marquee to play alongside former teammate Filip Hološko under the new 2 marquee rule. In addition to this, he also brought in 5 Australian players, including Bernie Ibini on loan, Socceroo Alex Wilkinson (two whom have worked with Arnold at the Central Coast) and Danny Vukovic from rival club Melbourne Victory. The season started off with a bang, with Sydney FC defeating their rivals Western Sydney Wanderers 4-0 in round 1. He led the team to a runners-up finish after being defeated 1-0 in the FFA Cup Final by Melbourne City.
Into the January transfer window, fan favourite Matthew Jurman joined K-League club Suwon Samsung Bluewings, while keeper Vedran Janjetović swapped with Andrew Redmayne to cross city rivals, Western Sydney Wanderers after a dispute about not playing after being displaced by Vukovic. To replace Jurman, Dutch defender Jordy Buijs signed. The team was able to go on undefeated for 19 games in the league before eventually being defeated 1-0 in a controversial game against the Wanderers. This defeat only made the team stronger, as they went the remainder of the season undefeated, gaining 19 points out of a possible 21 for the remaining 7 games. His team was eventually crowned premiers after Melbourne Victory was unable to defeat Brisbane Roar, while Sydney had 4 games remaining. Arnold's 3rd season with Sydney proved fruitful, in addition to winning the premiership, the squad had broken multiple records, including the most points in a single season, breaking Brisbane Roar's 2010-11 season of 65 points in 3 fewer games with 66 points, as well as being the only top-flight football team in Australia to stay outright 1st throughout the whole season. Arnold was also named Coach of the Year at the Dolan Warren Gala Night. He ended the season with a 1-1 in the Grand Final, winning 4-2 on penalties against Melbourne Victory, becoming the first manager to win the championship with more than one club.As of 16 April 2017
PlayerNSW Player of the Year: 1985
National Soccer League Player of the Year: 1986
National Soccer League Golden Boot: 1986
Football Hall of Champions: 2004
Central Coast Mariners
A-League Premiership: 2011–12
A-League Championship: 2013
A-League Premiership: 2016–17
A-League Championship: 2016-2017
FFA Cup Runners-Up: 2017
A-League Coach of the Year: 2011–12, 2016–17
A League All Star Team Manager: 2011-12
PFA Manager of the Season: 2011-12