Chris Boucher scored a career-high 38 points and had 19 rebounds for the Raptors. They have lost 15 of 18.
Pascal Siakam added 27 points and eight rebounds for Toronto.
Chicago ran off 13 straight points while the Raptors missed 10 straight shots, and a 3-pointer by Coby White made it 51-31 with 6:04 left in the first half.
Two 3-pointers and a three-point play by Boucher helped Toronto cut the margin to seven late in he fourth quarter, but LaVine closed it out with a layup and a 3-pointer with 45 seconds left.
Rookie Malachi Flynn got his first NBA start for the Raptors, who had only eight players available for the game. They signed Freddie Gillespie to a 10-day contract early Thursday, but the 6-foot-9 former G-League player had not cleared the NBA’s entry protocol in time to play.
WATCH | North Courts — Raptors mailbag: