Some lesbians and gay men tend to be more gender nonconforming, on average and for certain traits, than their heterosexual counterparts. Gender nonconformity in childhood has also been linked to adult homosexuality. Studies of both lesbians and gay men also find elevated rates of psychological distress. We hypothesized that these facts may be related. Individuals who violate social norms for gender-appropriate behavior may suffer from stigmatization by both heterosexual and homosexual people, leading to higher levels of psychological distress. We examined whether several measures of gender nonconformity were related to psychological distress in a community-based sample of gay men and lesbians. These included self-reports of childhood and adulthood gender nonconformity, as well as observer ratings of current behavior. Several measures of gender nonconformity were related to each other for both lesbians and gay men. In addition, gender nonconformity was related to psychological distress, but only for gay men. Finally, both lesbian and gay male participants reported more positive attitudes towards gender conformity than nonconformity, although the pattern was somewhat different for each group. We discuss the implications of these results for future studies of gender nonconformity and for the promotion of psychological health in lesbians and gay men.