BACKGROUND: HPV vaccination of men who have sex with men (MSM) prior to the commencement of sexual activity would have the maximum impact on preventing HPV and anal cancer in this population. However, knowledge and attitudes towards HPV vaccination among very young MSM have not been previously studied. METHODS: Two hundred MSM aged 16 to 20 were recruited via community and other sources. Participants were asked about their knowledge and attitudes towards HPV and HPV vaccination. RESULTS: Most (80%, 95% confidence interval (CI) 72.2-87.2%) men were not willing to purchase the vaccine because of its cost (AUD$450). However, if the vaccine was offered to MSM free of charge, 86% (95% CI: 80-90%) reported they would be willing to disclose their sexuality to a health care provider in order to obtain the vaccine. Over half (54%, 95%: 47-61%) of men would only be willing to disclose their sexuality to receive the HPV vaccine after their first experience of anal intercourse. The age at first insertive anal intercourse and the age at first receptive anal intercourse were 0.21 (IQR: -2.5 to 3.2) and 0.17 (IQR: -2.9 to 2.7) years earlier than the age that men would be willing to disclose their sexuality to receive the HPV vaccine, respectively. Willingness to receive the vaccine at a younger age was associated with younger age at first insertive anal intercourse. CONCLUSION: Overall, very young MSM expressed high acceptance of HPV vaccination. Early, opportunistic vaccination of very young MSM may be feasible in settings where very young MSM have not been vaccinated through universal programs targeting school aged males. However, given HPV infections occur early on, the effectiveness of this approach will be less than vaccination targeting school aged boys.