Adrienne Godbold led four Illini players in double figures with 16 points, and set up the win with a pair of free throws with 40 seconds left that gave Illinois a a 64-63 lead.
Hill scored 20 points to lead Ohio State (21-3, 8-3), who have now lost two out of the last three games. Ashley Adams tied a career high with 18 points and grabbed eight rebounds.