Disney Music Group chairman Bob Cavallo has announced his retirement, effective Jan. 31, 2012, after 13 years at the top of the company.

Mouse vet Ken Bunt has been promoted to exec VP and will head DMG after Cavallo’s retirement.

Walt Disney Studios chairman Rich Ross called Cavallo “a mentor and friend not only to those of us who have had the privilege of working with him here at Disney, but to the many artists he’s helped nurture and grow throughout his career.”

During his tenure, Cavallo merged Disney’s label, publishing and concert units into the centralized DMG. He helmed explosive growth of Disney’s music, as the company developed a heavyweight roster of tween-friendly acts, many of which spun off the company’s TV properties. Its top artists included the Jonas Brothers, Miley Cyrus, Selena Gomez, Demi Lovato and the Plain White T’s.

Before joining Disney, Cavallo was a prominent artist manager whose clients included Prince, Seal, Green Day, Weezer, Alanis Morissette and the Goo Goo Dolls.

Cavallo’s son Rob is chairman of Warner Music Group and a Grammy-winning producer.

Bunt is DMG’s longtime senior VP of marketing. He joined the company’s Hollywood Records imprint in 1998 after beginning his career at Rick Rubin’s Def American Recordings (later American Recordings).