Kelly Olynyk supplied 14 points and 11 rebounds for the Celtics, who broke open a tight contest by outscoring the Bucks 32-18 down the stretch.
Jared Sullinger and Phil Pressey helped out with 13 points each.
Milwaukee got 22 points from Brandon Knight but it wasn't enough to avoid an 18th loss in 20 games.
Notable deaths of 2014 [PHOTOS]
UPI Sports Results for September 19, 2014