Although scholarship continues to document higher rates of alcohol use for sexual and gender minority (SGM) youth compared with heterosexual and cisgender youth, research identifying factors that mitigate SGM youths' risk is nascent. Youth spend substantial time in schools; therefore, teachers could play significant roles in attenuating these health concerns. We used data from a nationwide survey of 11,189 SGM youth (Mage = 15.52; 67.7% White) to explore whether perceived teacher social-emotional support attenuated the association between victimization and alcohol use, further conditioned by youths' specific ethnoracial identity. As expected, victimization was associated with more frequent alcohol use; however, greater perceived teacher support attenuated this association. The attenuating effect of perceived teacher support was significantly stronger for Hispanic/Latinx youth than White youth. Our findings have implications for alcohol use prevention among SGM youth, who face significant marginalization in schools and society. If we are to prevent alcohol use disparities among SGM youth, scholars and stakeholders (e.g., school administrators, teachers) should invest in building teacher efficacy to intervene in SGM-specific victimization.