Reduction of unprotected anal intercourse (UAI) in gay men infected with HIV is important in preventing further spread of this infection. In previous studies, personality trait measures relevant to sexual arousability and the effects of anxiety have been shown to relate to UAI in both gay and heterosexual men. Are HIV+ gay men similar in these respects or are there other personality-related factors that influence their sexual risk taking? This question was addressed using a convenience sample of 156 HIV+ gay men and 155 HIV- gay men, matched for age and UAI risk. There were no significant differences between these two groups on measures of sexual arousability, inhibition of sexual arousal in risky situations, sensation seeking, depression and anxiety proneness, or tendency to increased sexual interest in negative mood states. HIV+ men were, however, more likely to report erectile problems and higher scores on an associated trait measure, inhibition of arousal due to threat of performance failure. As this association was not anticipated, questions about whether erectile problems preceded the seroconversion were not asked. Such problems could be associated with reluctance to use condoms, thus increasing the likelihood of seroconversion and/or disease transmission. Alternatively, erectile problems could be a consequence of HIV infection. In each case, this has implications for prevention. The associations among HIV status, erectile problems, and UAI need to be specifically addressed in future research.