Leading 37-24 at halftime, Baylor jumped to a 45-26 lead three minutes into the second half.
But Iowa State (15-12, 5-9 Big 12) responded with a 17-4 run and cut the margin to single digits at 49-43 with 12 1/2 minutes left to play.
The Bears regained control with a 10-3 outburst to make it 59-46 midway through the second half, and the Cyclones never cut their deficit to less than double digits.
Baylor's biggest advantage came at the free-throw line as the Bears converted 24 of their 30 attempts, while the Cyclones shot 14-of-16.
Four Baylor 3-pointers propelled the Bears to a 23-10 lead midway through the first half. The Bears maintained that margin and led 37-24 at halftime.