Most people living with HIV/AIDS (PLWHA) disclose their serostatus to their sexual partners and take steps to protect their partners from HIV. Prior research indicates that some PLWHA portray themselves to their sexual partners as HIV-negative or otherwise misrepresent their HIV status. The aim of this study was to document the prevalence of misleading sexual partners about HIV status and to identify factors associated with misleading. A sample of 310 PLWHA completed a self-administered questionnaire assessing demographic information, disclosure, HIV knowledge, HIV altruism, psychopathy, and sexual risk behavior. Participants were also asked "Since you were diagnosed as having HIV, have you ever misled a sexual partner about your HIV status?" Overall, 18.6% of participants indicated that they had misled a sexual partner. Those who had misled a partner at some point since their diagnosis reported more current HIV transmission risk behaviors, including unprotected anal or vaginal sex with a partner who was HIV-negative or whose HIV status was unknown. Participants who had misled a partner did not differ from those who had not in terms of demographic characteristics. Individuals who had misled a partner scored significantly lower on a measure of HIV knowledge than those who had not misled a partner. HIV altruism and psychopathy were associated with sexual risk behavior, but did not differ between those who had misled and those who had not. Disclosure of HIV status can reduce HIV transmission, but only if people are candid. Interventions aimed at increasing knowledge and accurate disclosure may reduce the spread of HIV.