This article presents empirical research findings from a subsample of 290 transgender participants in the Virginia Transgender Health Initiative Survey (THIS) who reported whether or not they had experienced hostility or insensitivity related to their gender identity or expression during high school, termed in-school gender-based victimization (GBV). The purpose of this study was to assess the impact of in-school GBV on rates of suicide attempts among transgender people. Of the 290 respondents, 44.8% reported they had experienced in-school GBV, and 28.5% reported a history of suicide attempt. Among those who had attempted, 32.5% reported having made one attempt, 28.6% reported a history of two attempts, and 39.0% reported having made three or more attempts. Participants who reported experiencing GBV were approximately four times more likely to have attempted suicide than those who did not. Among the subgroups of 147 trans women and 81 trans men, GBV was associated both with history of suicide attempt, and with a higher number of suicide attempts over the life span. Implications for policy and clinical interventions are discussed.