Will Cherry, Kareem Jamar and Mike Weisner added 10 points apiece for the Grizzlies (19-5, 15-1 Big Sky), who were coming off a loss at Weber State on Thursday that snapped their record 25-game Big Sky winning streak.
Melvin Morgan scored 14 points and Chris Hansen had 12 for Idaho State (5-20, 4-12).
Ward scored eight points during a 17-5 run that gave Montana a 29-22 lead at intermission. A 9-0 run early in the second half extended the lead to 38-24 on Spencer Coleman’s 3-pointer.
Idaho State closed to 50-42 on Ayibakuro Preh’s dunk with 7:58 remaining, then used a 10-4 run to come within 55-52 on Hansen’s 3-pointer with 2:33 left.
Weisner answered with a 3-pointer as Montana closed the game on a 6-2 run.