The Cowgirls (5-0) shot 51.7 percent from the field and had four players score in double figures. Liz Donohoe scored 15 points and Tiffany Bias had 14. Kendra Suttles finished with 10 points and a game-high 11 boards.
USC (3-1) was held to 18 of 54 shooting and had 19 turnovers. Ariya Crook was the only scorer in double figures for the Trojans with 12 points. Alexyz Vaioletama scored eight and pulled in seven rebounds.
Oklahoma State never trailed in the game as LaShawn Jones hit a jumper to open the scoring. Following a Crook layup to tie it at 2, the Cowgirls surged to a 20-4 lead sparked by three baskets from Martin and two 3-pointers from Donohoe.