The Cyclones weren't intimidated by the top-ranked team in the land from the opening, holding a 14-12 lead at the 12:39 mark after Diante Garrett buried back-to-back 3-pointers.
ISU continued to hang around later in the half, as KU was up 31-25 with 2:08 left in the first period. However, the Jayhawks scored the final four points of the first half, including a lay-up by Sherron Collins in the final seconds, to give the home team a 35-26 halftime advantage.
The Cyclones had their chances to shrink the gap a little closer, but made just 6-of-12 shots from the foul line in the opening period.
ISU started to chip away at the lead, outscoring KU 12-5 to open the second half to make it 40-38 KU with 13:32 left in the game. Craig Brackins scored five points in the second-half surge on an alley-oop dunk off a Garrett feed and a deep trey in the corner.
But less then two minutes later, the Jayhawk lead was back up to 11 points thanks to a swift 9-0 run. Brady Morningstar started the flurry with a steal and lay-up and Tyrel Reed capped it off with a running bank shot to make it 49-38 KU with 11:09 left in the game.
KU rattled off 14-straight points before Justin Hamilton stopped the run with a baseline jumper to make to cut the lead to 54-40 with 9:15 left in the contest. The Jayhawks stretched the lead to 20 points soon after to put any chance of an ISU upset bid out of reach.
Brackins finished the game with his fourth double-double in the last five games with 18 points and 10 boards. Hamilton also added a double-double, his second of the season, with 11 points and 12 caroms.
Iowa State plays host to Oklahoma State on Feb. 17.