Thirty-two college students (16 male, 16 female) had EEG recorded during computerized two- and three-dimensional mental rotation tasks. The simple two-dimensional mental rotation task was associated with more left parietal than right parietal activation in men and more right parietal than left parietal activation in women. The complex three-dimensional mental rotation task was associated with greater right parietal than left parietal activation in both men and women. Men performed better than women on the three-dimensional task and there were no differences between men and women on the two-dimensional task. It was concluded that men and women may be using different neurological strategies on two- and three-dimensional mental rotation tasks.