Research has demonstrated a relationship between sexual orientation and poor mental health outcomes among young adults (McLaughlin, Hatzenbuehler, Xuan, & Conron, 2012). However, gender nonconformity is highly correlated with sexual orientation among youth (Rieger & Savin-Williams, 2012), and may be a predictor of mental health concerns among young people, regardless of sexual identity or behavior (Bos & Sandfort, 2015). This study explores the possibility that gender nonconformity—as measured by the masculinity and femininity subscales of the Bem Sex Role Inventory (BSRI; Bem, 1974)—may help to explain the variance observed in depression and suicidality in the Center for Disease Prevention and Control’s National Longitudinal Study of Adolescent Health (Add Health). Hierarchical regression analysis on a sample of 7,167 men in Wave III of the study revealed that while self-reported sexual identity and romantic attraction did predict depressive symptoms, suicidal behavior could not be accounted for by these variables alone. Adding BSRI masculinity and femininity scores did not help account for the variance observed in depression or suicidality, either alone or in interaction with measures of sexual orientation. In order to evaluate the predictive power of the BSRI in determining mental health outcomes among gay and straight young adults, a more nuanced measure of lifetime sexual orientation is proposed. Also, a longitudinal approach is recommended for the inclusion of other outcome and possible explanatory variables, one that prioritizes other mental health outcomes like self-esteem and anxiety, in addition to predictors like subjective social status, parental educational attainment, and youth and adult urbanicity. Ramifications for social work research and leadership are discussed.