The two-time All-NBA selection and four-time all-star joins a decorated Golden State locker room coming off of its second consecutive NBA title and third championship in four years.
Cousins, 27, played the first six seasons of his career with the Sacramento Kings before he was traded to the New Orleans Pelicans in February 2017. He posted 25.2 points, and a career-high 12.9 rebounds and 5.4 assists per game last season.
Cousins played in 48 games last season before tearing his achilles tendon on Jan. 26 and ending his season. He is expected to be out until December or January, according to ESPN. Cousins was also considering a move to the Boston Celtics.
Golden State used its taxpayer mid-level exception to reach a deal with the 6-foot-11 center.
Cousins' signing came a day after four-time NBA MVP LeBron James announced he would sign with the Los Angeles Lakers. The Lakers have also added Rajon Rondo, Lance Stephenson, Kentavious Caldwell-Pope and JaVale McGee.