Comcast SportsNet California made the announcement on Thursday.
Chavez will work as a color commentator on 20 telecasts, starting April 24 when the A's host Houston. He also will be a studio analyst for some pregame and postgame shows.
Chavez made his major league debut in 1998 with Oakland and played his first 13 seasons with the A's. He won six straight Gold Gloves.
The 37-year-old Chavez played 44 games for Arizona last season and hit .246.