Curry attended Eastern Alamance High School, in Mebane, North Carolina, where he set the all-time North Carolina high school scoring record with 3,307 points.
He averaged 40.2 points, 7.3 rebounds, and 6.0 assists per game as a senior and was a two-time Associated Press All-State first team selection.
Curry scored an OSU freshman all-time NCAA Tournament-best 18 points in the 2005 second-round game against Southern Illinois on March 20, 2005.
He helped Oklahoma State to a 26–7 record, the Big 12 Tournament crown and the 2005 NCAA Sweet Sixteen as a freshman in 2004–05; he started 15 of 33 games played and averaged 9.4 ppg. and 2.8 apg. and averaged 14.3 ppg. in three 2005 NCAA games.
He finished the season ranked ninth among Big 12 leaders in conference games for 3-point field goals made (1.75 per game).
He scored 22 points on 8-for-11 shooting, in his first start versus Colorado on January 30, 2005. He made six three-pointers out of 8 attempts, including 5-for-5 in the second half, in which he scored 17 of his 22. He matched his career-high 22 points in a 79–67 victory over Oklahoma on February 7, 2005.
In his freshman season, Curry scored in double digits in 15 games, including twice over 20 points.
Highlights of his sophomore season include a career-high 30 points in a 97–61 victory over Mercer on December 18, 2005, and a 22-point, nine-rebound effort in an 81–60 win over Texas on February 19, 2006. He recorded a double-double, scoring 16 points and making a career-high 10 assists in a 90–56 win over Detroit on November 22, 2005, and matched that assists total against Gonzaga in a 64–62 loss on December 10, 2005.
In his junior season, on November 29, 2006, Curry scored a career-high 35 points (on 12-for-19 shooting) to go along with a season-high 9 assists with no turnovers in a 95–73 win over Texas A&M-Corpus Christi. On January 16, 2007, Curry scored 28 points and grabbed a season-high 9 rebounds in 52 minutes played in a 105–103 triple-overtime win over Texas. On March 3, 2007, Curry scored a new career-high 40 points, including a career-high 7 three-pointers out of ten attempts, in an 86–82 loss to Baylor.
The Chicago Bulls selected Curry with the 51st overall pick of the 2007 NBA draft. On August 2, 2007, the Bulls announced that Curry had signed a contract and will wear number 20. Per team policy, terms of the contracts were not disclosed.
On July 31, 2008, the Bulls waived Curry. By releasing him, the Bulls were only obligated to pay $100,000 of his partially guaranteed salary for 2008–09.
In August 2008, he was signed by Pau-Orthez of the French league, but was waived in October after failing to impress coaching staff. He later joined Proteas EKA AEL, a Cypriot team in Limassol.
On January 22, 2010, Curry was signed by the Los Angeles Clippers out of the Springfield Armor, for whom he had been averaging 16.1 points, 7.5 assists and 4.0 rebounds. He was released by the Clippers on January 26, when the team acquired Bobby Brown. He only played a total of 3.9 seconds during his tenure.
The Bulls assigned Curry to their NBA Development League affiliate Iowa Energy on November 15, 2007, then recalled him to the NBA on December 17 but soon after reassigned him to Iowa on January 7, 2008. He was recalled later that month. Curry played 13 games as a starter for Iowa during the 2007–08 season, averaging 20.2 points, 3.2 rebounds, 5.6 assists and 1.08 steals per game in 39.7 minutes per game. He also shot .463 from the floor, including .377 from three-point range, and .719 from the free throw line. Curry was selected 14th overall in the 2009 NBA D-League Draft by the expansion Springfield Armor on November 5. It was their first-ever pick. Curry was selected to play in the 2012 NBA D-League All-Star Game in Orlando.
On November 1, 2013, he was re-acquired by the Springfield Armor. On January 2, 2014, he was traded to the Bakersfield Jam. On March 19, 2014, he was waived by the Jam due to a season-ending injury.
In February 2004, Curry was among 49 students arrested in a drug raid that involved North Carolina's Alamance County school system. He was charged with two counts of possession with intent to sell and deliver marijuana, two counts of sale and delivery of marijuana, and two counts of sale, possession, and delivery of a controlled substance on school grounds. Curry pleaded guilty to the drug charges, and the University of North Carolina, with whom he had signed a letter-of-intent, rescinded the scholarship to him.
In the early morning of January 17, 2008, he was arrested in Boise, Idaho and pleaded guilty to resisting arrest and urinating in public. Police took him to the Ada County jail. He was released a few hours later after posting $600 bond. The Chicago Bulls suspended him one game after he pleaded guilty to the two misdemeanors.
On October 20, 2014, Curry was arrested for marijuana possession and false representation to an officer in Edmond, Oklahoma.
JamesOn Curry was brought up on a tobacco farm in rural North Carolina in Pleasant Grove. His first name is a mix of Leon and James, honoring his father and grandfather, respectively.