Matched groups of homosexual men, heterosexual men, and heterosexual women (n = 38 per group) were tested on three measures of spatial ability and two measures of fluency that typically reveal sex differences. For the three spatial tests and one of the fluency tests, the mean performance of homosexual men fell between those of the heterosexual men and women. The pattern of cognitive skills of homosexual men was different from that of heterosexual men: homosexual men had lower spatial ability relative to fluency. The cognitive pattern of homosexual men was not significantly different from that of heterosexual women. In addition, the results suggest that homosexual men classified on the basis of hand preference may form two subgroups that differ in cognitive pattern. These findings are compatible with the hypothesis that there is a neurobiological factor related to sexual differentiation in the etiology of homosexuality.