Pierce replaces Stephen Silas, who left the club to work under his father and new Bobcats coach Paul Silas.
The 34-year-old Pierce, a Bay Area native, helped Santa Clara to a pair of NCAA tournament appearances during his collegiate career. He spent the past three seasons as player development coordinator for the Cleveland Cavaliers.
Paul Silas became Charlotte's interim coach on Wednesday, replacing the fired Larry Brown.
Golden State announced its new assistant on Friday.