The Warriors announced Barbosa's signing Monday. The contract is worth about $2.5 million.
The 32-year-old combo guard is one of coach Steve Kerr's favorites from their time together in Phoenix, where Kerr was the general manager. The Brazilian-born Barbosa averaged 7.1 points and 1.5 assists in 14.9 minutes last season with the NBA champion Warriors.
He served as a reserve behind MVP Stephen Curry and All-Star guard Klay Thompson. Barbosa also played for Toronto, Indiana, Boston and Phoenix again in 2013-14 before joining Golden State last summer.
Barbosa has averaged 11.4 points, 2.3 assists and 2.1 rebounds in his 12-year career.