Sexual minorities report poorer mental health relative to heterosexual counterparts, but this is underexplored in Latinx youth. This study compares internalizing symptoms and externalizing behaviors in Latinx adolescents with Same Sex Behaviors (LASSB) to their Latinx adolescent peers who did not report same sex behaviors (non-LASSB). It also explores the moderating role of biculturalism on the relationship between internalizing symptoms and externalizing behaviors, and same-sex behaviors. Individual-level baseline data (Total N = 1,634; LASSB n = 195) from five trials of a preventive intervention for Latinx adolescents were synthesized. Normal and clinical levels of internalizing symptoms and externalizing behaviors were determined, and logistic regression models were conducted to determine the odds of LASSB reporting these behaviors relative to non-LASSB. Additional adjusted models tested for the moderating effect of biculturalism. LASSB reported significantly higher odds of normal levels of all externalizing behaviors and clinical levels of anxious/depressed compared to non-LASSB. Biculturalism significantly moderated the association between same-sex behavior and clinical levels of internalizing behaviors; however, in subgroup analyses among LASSB, biculturalism did not significantly predict any of these behaviors. Latinx adolescents exhibited mental health disparities by same-sex behavior. Biculturalism may be an important indicator for describing these disparities in LASSB and should be further explored.