Dempster will now become a special assistant to president Theo Epstein and general manager Jed Hoyer.
The 37-year-old has not pitched in the majors since 2013, when he started 29 games for the Boston Red Sox and went 8-9 with a 4.57 ERA. He had a 16-year MLB career, including nine seasons with the Cubs from 2004-2012.
Dempster retires with a won-loss record of 132-133, a 4.35 career ERA and 2,075 strikeouts in 2,387 innings. In his nine years in Chicago, Dempster went 67-66 with a 3.74 ERA.
The Canada-native also spent time with the then-Florida Marlins, Cincinnati Reds, Texas Rangers and Red Sox. He was originally drafted by the Rangers in the third round of the 1995 amateur draft and made his major league debut in 1998 with the Marlins.
In 2013, Dempster won a World Series while with Boston, appearing in three games in the postseason.
- Molly Geary