After his freshman year with the Georgia Tech Yellow Jackets, he was selected as the 4th overall pick in the 1996 NBA draft by the Milwaukee Bucks, but was traded shortly thereafter to the Minnesota Timberwolves.

Jealous of Garnett's contract, Marbury demanded a trade and was dealt to the New Jersey Nets, where he made his first All-Star and All-NBA Team.

He was then dealt to his hometown team New York Knicks where he became hated, leading him to leave the NBA for the Chinese CBA, where he became a superstar.

[3] He was often heralded as the next great NYC point guard, expected to follow the success of NBA stand-outs Mark Jackson and Kenny Anderson.

He was named a 1995 McDonald's All-American along with future NBA All-Stars Kevin Garnett, Paul Pierce, Shareef Abdur-Rahim, and Antawn Jamison.

Marbury was listed as one of the top five recruits in the country that year and was pursued by Georgia Tech Yellow Jackets coach Bobby Cremins, with whom he eventually committed.

[4] Teaming with future NBA players Matt Harpring and Drew Barry, Marbury led Georgia Tech to a 24–12 record en route to the Regional Semi-final game of the NCAA tournament, where the Yellow Jackets lost to Cincinnati 87–70.

For the season, Marbury averaged 18.9 ppg and 4.5 assists and was named a Third Team All American by the Associated Press, along with several conference honors.

Other reports said he wanted to go to a market that would provide more endorsement opportunities, while others suggested that Marbury genuinely disliked Minnesota and was jealous of Kevin Garnett's new contract.

[6][7] Marbury was ultimately traded to the New Jersey Nets, alongside Bill Curley and Chris Carr of the Timberwolves and Elliot Perry of the Milwaukee Bucks in a three-way trade where the Timberwolves acquired Terrell Brandon, Brian Evans and draft considerations and the Bucks acquired Sam Cassell and Chris Gatling.

Marbury was traded to the Phoenix Suns along with Johnny Newman and Soumaila Samake in the 2001 offseason for Jason Kidd and Chris Dudley.

On November 30, 2002, Marbury scored a season-high 43 points, including 26 in the 4th quarter, to lead the Suns to a 94–87 win over the San Antonio Spurs.

The pivotal incident involved Marbury leaving the team after learning that Thomas planned to remove him from the starting lineup.

The dysfunction and drama were accompanied by 8 straight Knicks losses, and several newspapers reported that Isiah's job was in jeopardy.

[21] In his first game, Marbury, suffering from jet lag, contributed 15 points, 4 rebounds, 8 assists, and 4 steals in 28 minutes of action.

[25] Like the previous season, Marbury played in the starting five of the 2011 CBA All-Star match, but his team failed to make the playoffs.

Averaging 45 points per game during the Shanxi series, Marbury led Beijing to their first ever CBA Finals match-up against the 7-time champion Guangdong Southern Tigers.

[26] Following the team's championship, in May 2012, a statue of Marbury was unveiled on the lawn of the MasterCard Center, the 2008 Olympic basketball arena, in Beijing.

However, on February 11, 2018, Marbury played his final game in the CBA, scoring 20 points in a 104–92 win over the Jiangsu Dragons, and announced his retirement from basketball.

[35] On June 24, 2019, Marbury was named head coach of the Beijing Royal Fighters of the Chinese Basketball Association (CBA).

[37] On March 8, 2020, Marbury warned NBA Commissioner Adam Silver to stop the 2019–2020 season, saying, "the game won't be fun if people die."

[48] In 2020, during the COVID-19 pandemic, Marbury worked with a China supplier to sell millions of masks at cost to assist first responders and hospital workers in New York City.

[52] In May 2017, Marbury expressed interest in helping Big Baller Brand partner with a Chinese sports apparel company.

In the Spike Lee movie He Got Game, fictional Brooklyn high school star Jesus Shuttlesworth (played by Ray Allen) mentions Stephon Marbury as one of the great New York City legends to make it out of Coney Island to the NBA.

In 1999, Marbury, alongside fellow former Georgia Tech point guard Kenny Anderson, appeared in the video for Big Pun's single "Whatcha Gonna Do" which was produced by Juju of The Beatnuts.

In the video, Marbury and Anderson play a 2 on 2 game versus Terror Squad members Fat Joe and Cuban Link.

In 2007, Marbury co-authored his first children's book with Marshall Dean entitled The Adventures of Young Starbury: Practice Makes Perfect.

[55] In July 2009, Marbury engaged in a 24-hour live-streaming broadcast[56][57] in which he answered questions from fans, openly wept, and ate vaseline to soothe a sore throat.

[63] On October 20, 2017, it was announced that Marbury had reached an agreement to become the owner of the Beijing Lions of the China Arena Football League.