Kevin Larsen added 14 points and Tyler Cavanaugh 11 for the Colonials, who shot 52 percent. Cavanaugh and Joe McDonald had eight boards apiece in leading a 37-25 advantage on the boards.
George Washington (11-2) has won five out of its last six games as it heads into its Atlantic 10 opener against Fordham on Sunday.
The Knights (6-5) were led by Tanksley Efianayi with 12 points and Shaheed Davis with 11 as UCF shot just 35 percent. UCF lost for only the second time in seven games and begins American Conference play Saturday at East Carolina.
Yuta Watanabe hit a 3-pointer to give the Colonials the lead for good at 30-28 late in the first half. They outscored UCF 25-7 over the first 13 minutes of the second half to lead 59-38.