George Washington (18-10, 8-7) moved ahead the Bonnies (14-12, 7-8) in the Atlantic 10 Conference standings, and now sit a game behind Massachusetts and Richmond and three games back of a four-team tie for first. The top four teams in the A10 earn a double bye into the conference tournament semifinals.
The Colonials doubled up St. Bonaventure in the first half, taking a 36-18 lead into halftime.
George Washington shot a red-hot 57.8 percent from the field, knocking down 26 of 45 shots from the field and 10 of 18 from beyond the arc. Kevin Larsen had 14 points and John Kopriva added another 13.
Marcus Posley scored 12 points to lead St. Bonaventure. Dion Wright and Andell Cumberbatch each added 10 points.