Stigma within health care settings poses a considerable barrier to the provision of treatment and care for patients with HIV/AIDS (PLWHA). Southern China is located in a region with one of the world's fastest growing HIV/AIDS epidemics. Attitudes towards PLWHA amongst health workers are currently under-researched in this region. This paper examines the inter-relationships between prejudicial attitudes among Chinese medical students towards HIV/AIDS and attitudes towards three risk behaviors: injecting drug use (IDU), commercial sex (CS) and commercial blood donation (CBD). Medical students (N = 352) in Guangzhou were presented with two random vignettes; each describing a hypothetical male that was identical, except for the disease diagnosis (AIDS/leukemia) and the co-characteristic (IDU/CS/CBD/blood transfusion/no co-characteristic). After reading each vignette, participants completed a standard prejudicial scale. Univariate and multivariable analyses revealed significant levels of prejudice associated with AIDS, IDU and CS. Regardless of the disease, patients with IDU or CS were judged significantly worse than patients who had received a blood transfusion. No significant interactions were found between AIDS and the stigmatized co-characteristics. The findings suggest that prejudice towards PLWHA needs to be understood within the larger context of the stigma towards risk behaviors. Although non-significant interactions were found between AIDS and the stigmatized risk behaviors, the overlap between the local HIV/AIDS, IDU and CS populations suggests that addressing risk behavior-related prejudices could be critical for improving care and treatment for PLWHA.