Exposure to comprehensive sex education shows promise in preventing sexual violence and sexual harassment (SVSH) perpetration and victimization and supporting survivors. Determining if these benefits are also found in communities experiencing high levels of SVSH, such as lesbian, gay, bisexual, transgender and queer (LGBTQ+) communities, is needed. Utilizing a sequential explanatory mixed-methods study design, we assessed LGBTQ + undergraduates' exposure to sex education (SE), what SE sources they relied on, and SE's perceived usefulness and responsivity to LGBTQ + needs. Compared to their non-LGBTQ + peers, LGBTQ + students perceived SE as less helpful in navigating personal desires (t294 = 2.08, p < 0.05) and sexual consent (t295= 2.15, p < 0.05). LGBTQ + students were more likely to use media (e.g., internet, pornography) as their primary source of SE on topics such as violence in relationships and consent. In-depth interviews substantiated quantitative findings, highlighting the non-responsiveness of SE among LGBTQ + students and further revealed that having to supplement SE through media increased LGBTQ + students' vulnerability to SVSH (including online sexual coercion). Via interviews, LGBTQ + students reported formal SE to be non-inclusive, led to experiences of othering, silencing, erasure, and made them more vulnerable to SVSH and related outcomes. SE policy and education must be modified to be more inclusive and helpful for LGBTQ + students, especially relating to SVSH prevention.