Baker had a 3-point play during a 10-0 run early in the second half for a 51-37 lead. VanVleet tied his career best on a 3-pointer with eight minutes left and set the mark one minute later on a layup.
Anton Grady's layup with 3:34 remaining gave Wichita State its largest lead of the game at 22 points.
Wichita State (12-5, 6-0 Missouri Valley) made just 41 percent of its shots but went 28 of 34 from the stripe (82 percent).
Brenton Scott led Indiana State (10-8, 4-2) with 24 points and had four 3-pointers. Devonte Brown added 14 points for the Sycamores, who trailed by just five points at halftime but were held to 8-of-29 shooting (27.6 percent) in the second half.