The American guard, a 3-point sharpshooter who hit 40% from beyond the arc over his career, announced his decision on social media.
"I knew this day would eventually come," Green wrote. "My life has revolved around this game, taking me all over the world and introducing me to incredible people. It's been one helluva journey.
"I'm excited for the next chapter and look forward to conquering new challenges."
Green played for the 2014 NBA champion San Antonio Spurs, the 2019 champion Toronto Raptors and the 2020 champion Los Angeles Lakers, when he and teammate LeBron James joined Robert Horry and John Salley as the only players to win titles on three different NBA clubs.
Over 832 NBA games, 709 as a starter, Green averaged 8.7 points, 3.4 rebounds, 1.5 assists and 1.0 steals a game.
He played 20 games as a rookie for Cleveland before joining San Antonio, where he spent eight seasons before going to Toronto along with Kawhi Leonard.
He was signed by the Lakers in 2019 and later spent time with Philadelphia, Memphis and Cleveland.
