The main objective of the study was to investigate the relationship between selected sociodemographic factors (i.e. sexual orientation, gender and AIDS status), and the level of HIV/AIDS stigma among people living with HIV (PLWH). The participants were 663 adults with a medically confirmed diagnosis of HIV infection, undergoing antiretroviral treatment. Their level of HIV/AIDS stigma was assessed with the Berger HIV Stigma Scale, and relevant sociodemographic and clinical data were obtained using a self-report survey. The main effect was revealed only for sexual orientation and total stigma; those with heterosexual orientation declared higher levels of total stigma than those with other sexual orientations. For the subscales, significant results were obtained only for disclosure concerns. Namely, for the interaction of gender and sexual orientation, the highest level of disclosure stigma was declared by heterosexual women, while there was no such relationship for men. This result was further modified when AIDS diagnosis was added to the interaction. There is a cumulative effect of PLWH minority statuses, rather than main effects of each status individually. Thus, each minority status should be analysed from at least two perspectives, general (i.e., compared to the general population) and relative (i.e., compared to the population in question).