This short-term prospective study examined general and lesbian, gay, bisexual, and transgender (LGBT)-specific risk and protective factors for suicide attempts in an ethnically diverse sample of LGBT youth (N = 237, 47.7 % male). A structured psychiatric interview assessed clinical depression and conduct disorder symptoms, as well as past and prospective suicide attempts over a 1-year follow-up period (91 % retention). Participants completed questionnaires measuring general risk factors for suicide attempts, including hopelessness, impulsiveness, and perceived social support. They also completed measures of LGBT-specific suicide risk factors, including gender nonconformity, age of first same-sex attraction, and LGBT victimization. Correlation and multivariate regression analyses were conducted to examine the relations between predictors and suicide attempt, and to identify mediators. Of nine variables examined, seven were related to lifetime history of attempted suicide: hopelessness, depression symptoms, conduct disorder symptoms, impulsivity, victimization, age of first same-sex attraction, and low family support. Depressive symptoms and hopelessness mediated the relation between multiple risk and resilience factors and suicide attempts. Suicide attempt history was the strongest predictor of prospective suicide attempts. Participants who previously attempted suicide (31.6 % of the sample) had more than 10 times greater odds of making another attempt in the 1-year follow-up period than were those who had made no previous attempt. These results highlight the need for suicide prevention programs for LGBT youth and suggest the importance of addressing depression and hopelessness as proximal determinants and family support and victimization, which have more distal effects.