Ethiopia has a high prevalence of HIV/AIDS. Single-point estimates show adult HIV prevalence of 2.1 per cent for 2007. The 2005 Ethiopia Demographic and Health Survey (EDHS 2005) had indicated a national-level adult prevalence rate of 1.4 per cent among adults aged between 15 and 49 years (6 and 0.7 per cent in urban and rural residents, respectively). The rate in the capital, Addis Ababa, was 5 per cent. We conducted an ethnographic study to explore the possible role of men having sex with men (MSM) in the epidemiology of HIV/AIDS in the city of Addis Ababa, Ethiopia. To collect data, we used four focus group discussions with MSM, six key informant interviews, and extended observations at different places in Addis Ababa. These data were analyzed using open code software and a ‘grounded theory’ approach. We found that contextual factors, such as sociocultural background and politicolegal situation, predisposed to HIV/AIDS-related risk behavior among members of the study subgroup. The infection might have been transmitted between the study population and heterosexual people in the community by many possible routes. The study showed that men have sex with men among a segment of Addis’ population. The portion of the population involved is non-negligible. They are exposed to HIV/AIDS risks. It is, therefore, high time that the issue be openly discussed in the context of current efforts to control the HIV pandemic.