Social research with people living with HIV (PLHIV) rarely distinguishes between gay men and bisexual men. However, bisexual men may have unique experiences of HIV-related stigma and distinct support needs. In this paper, findings are presented from a cross-sectional survey of Australian PLHIV, which included the Berger (HIV) stigma scale. A total of 872 PLHIV completed the survey, of which 48 (6.0%) were bisexual men. Bisexual men reported higher levels of internalised HIV-related stigma, greater negative self-image and poorer emotional wellbeing than gay men. Bisexual men also reported less social support, less connection with lesbian, gay, bisexual, transgender and queer (LGBTQ) communities, and less connection with other PLHIV. Analysis of data from an open-text question revealed feelings of social isolation and fear of rejection was associated with participant's HIV diagnosis. Study findings suggest that existing social supports for PLHIV may not adequately address the unique support needs of bisexual men.