We know little about men's beliefs about human papillomavirus (HPV) vaccine and willingness to receive it. In January 2009, the authors recruited 296 heterosexual men and 312 gay and bisexual men from a national panel of U.S. households to complete an online survey about HPV and HPV vaccine. The authors analyzed data using logistic regression, controlling for age, education, number of lifetime sexual partners, and urban residence. More gay and bisexual men than heterosexual men were willing to receive HPV vaccine (73% vs. 37%; adjusted odds ratio = 4.99; 95% confidence interval = 3.36, 7.49). Gay and bisexual men reported greater awareness of HPV vaccine, perceived worry about HPV-related diseases, perceived effectiveness of HPV vaccine, and anticipated regret if they declined vaccination and later developed HPV-related disease compared with heterosexual men (all ps < .05). The lower acceptability and different beliefs among heterosexual men suggest that novel interventions for this group may be needed.