Chris Allen and Scott Christopherson scored 10 points each for the Cyclones (5-1). Melvin Ejim had eight points and 11 rebounds.
Tamir Jackson scored 13 points and Lucas Kuipers 11 for the Owls (4-2).
Allen’s 3-pointer with 13:30 remaining in the first half commenced a 13-0 run that gave the Cyclones permanent control of the game. McGee ended the surge with consecutive 3-pointers, the second giving Iowa State a 26-16 lead.
The Cyclones led by 29 points in the second half.