In Brazil, the inclusion of minorities and the most vulnerable members of the population in the health service is still a challenge for health planners. This study analyzed the perception of men who have sex with men (MSM) treated in health units with the onset of a sexually transmitted disease (STD). It consists of qualitative research involving 21 MSM, contacted in a non-governmental organization (NGO) and in the Testing and Counseling Center (TCC) in Fortaleza, Ceará, Brazil. The data were collected during two periods: from February until May 2007 and from September until October 2008 by using focused interview, and were organized by subject matter according to the content analysis technique of Bardin. The references to the theoretical concepts of the symbolic violence by Bourdieu and stigma by Goffman were the foundation for the analysis. The results indicate that MSM experienced situations of symbolic violence and avoided seeking primary health care service fearing prejudice and being stigmatized. Even when they sought these services, they tended to demonstrate masculine behavior in order to not be indentified as to their sexual orientation. We concluded that MSM feel excluded and discriminated against in the primary health care service. More studies related to this subject matter are needed to help implement health care policies facilitating the inclusion of and to welcome this group of the population into the general health care service.