Importance:Sexual minority men have reported higher rates of both indoor tanning and skin cancer than heterosexual men, and sexual minority women have reported lower or equal rates of both indoor tanning and skin cancer compared with heterosexual women. Bisexual men, in particular, have reported higher rates of indoor tanning bed use than heterosexual men; however, no study has investigated skin cancer prevalence among gay, lesbian, and bisexual individuals as separate groups. Objective:To evaluate the association between sexual orientation and lifetime prevalence of skin cancer. Design, Setting, and Participants:This cross-sectional study analyzed data from the 2014-2018 Behavioral Risk Factor Surveillance System (BRFSS) surveys of a noninstitutionalized population in the United States that included 877 650 adult participants who self-identified as being heterosexual, gay, lesbian, or bisexual. Main Outcomes and Measures:Self-reported lifetime history of skin cancer. Results:The study included 877 650 participants, including 364 833 heterosexual men (mean age, 47.7; 95% CI, 47.5-47.8), 7823 gay men (mean age, 42.7; 95% CI, 41.8-43.6), 5277 bisexual men (mean age, 39.4; 95% CI, 38.4-40.5), 484 341 heterosexual women (mean age, 49.7; 95% CI, 49.6-49.8), 5609 lesbian women (mean age, 41.8; 95% CI, 40.6-43.0), and 9767 bisexual women (mean age, 32.8; 95% CI, 32.3-33.3). The adjusted odds ratios (AORs) of skin cancer prevalence were significantly higher among both gay (AOR, 1.25; 95% CI, 1.03-1.50; P = .02) and bisexual men (AOR, 1.46; 95% CI, 1.01-2.10; P = .04) compared with heterosexual men. The AORs of skin cancer were statistically significantly lower among bisexual women (AOR, 0.75; 95% CI, 0.60-0.95; P = .02) but not among gay or lesbian women (AOR, 1.01; 95% CI, 0.77-1.33; P = .95) compared with the AORs of skin cancer among heterosexual women. Conclusions and Relevance:In this study, gay and bisexual men had an increased self-reported lifetime prevalence of skin cancer compared with the prevalence among heterosexual men. Patient education and community outreach initiatives focused on reducing skin cancer risk behaviors among gay and bisexual men may help reduce the lifetime development of skin cancer in this population. Continued implementation of the Behavioral Risk Factor Surveillance System's sexual orientation and gender identity module is imperative to improve understanding of the health and well-being of sexual minority populations.