IMPORTANCE Skin cancer, the most common cancer in the United States, is highly associated with outdoor and indoor tanning behaviors. Although indoor tanning has been suggested to be more common among sexual minority (self-reported as homosexual, gay, or bisexual) men compared with heterosexual men, whether rates of skin cancer vary by sexual orientation is unknown. OBJECTIVE To investigate whether skin cancer prevalence and indoor tanning behaviors vary by sexual orientation in the general population. DESIGN, SETTING, AND PARTICIPANTS We performed a cross-sectional study using data from the 2001, 2003, 2005, and 2009 California Health Interview Surveys (CHISs) and the 2013 National Health Interview Survey (NHIS) of population-based samples of the California and US noninstitutionalized civilian population. Participants included 192 575 men and women 18 years or older who identified as heterosexual or a sexual minority. MAIN OUTCOMES AND MEASURES Self-reported lifetime history of skin cancer and 12-month history of indoor tanning. RESULTS The study included 78 487 heterosexual men, 3083 sexual minority men, 107 976 heterosexual women, and 3029 sexual minority women. Sexual minority men were more likely than heterosexual men to report having skin cancer (2001-2005 CHISs: adjusted odds ratio [aOR], 1.56; 95%CI, 1.18-2.06, P < .001; 2013 NHIS: aOR, 2.13; 95%CI, 1.14-3.96, P = .02) and having tanned indoors (2009 CHIS: aOR, 5.80; 95%CI, 2.90-11.60, P < .001; 2013 NHIS: aOR, 3.16; 95%CI, 1.77-5.64, P < .001). Sexual minority women were less likely than heterosexual women to report having had nonmelanoma skin cancer (2001-2005 CHIS: aOR, 0.56; 95%CI, 0.37-0.86, P = .008) and having tanned indoors (2009 CHIS: aOR, 0.43; 95%CI, 0.20-0.92, P = .03; 2013 NHIS: aOR, 0.46; 95%CI, 0.26-0.81, P = .007). CONCLUSIONS AND RELEVANCE Sexual minority men indoor tan more frequently and report higher rates of skin cancer than heterosexual men. Primary and secondary prevention efforts targeted at sexual minority men might reduce risk factors for, and consequences of, skin cancer.