"This has been the ride of a lifetime," said Welts. "To have had a front row seat to the growth of the NBA from where it was in the late 1960s to its place today as one of the most respected and successful leagues in sports on a global stage has been an incredible privilege."
The 68-year-old led business operations for the Warriors for 10 seasons, overseeing the team's championship run and construction of Chase Center.
He has spent 46 seasons with three teams and the NBA league office.
Welts was inducted into the Basketball Hall of Fame in 2018, and in 2011 became the highest-ranking executive in men's professional team sports to publicly acknowledge he is gay.
Welts will step down at the end of the season.
The Warriors are expected to name a new president within the next week.
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