According to official Swiss data an increasing number of HIV-positive migrants reside in Switzerland. The present study examined epidemiologic, clinical, and migration-specific characteristics of HIV-infected migrants at the HIV clinic of the University Hospital of Berne, which is one of the centers of the national, prospective Swiss HIV cohort study. Data were collected by chart review. Among the 1331 patients the proportion of northwestern European patients decreased from 88% before 1989 to 67% in the late 1990s while the number of patients from sub-Saharan Africa and Southeast Asia increased from 3 (1.6%) to 47 (14%) and from 2 (1%) to 17 (5%), respectively. Sub-Saharan Africans and Southeast Asians were more likely to be younger, female, and infected heterosexually. At first clinical visit the various patient groups did not differ in CD4 counts or HIV RNA levels. Sub-Saharan African patients were more likely to be anemic. A majority of HIV-positive migrants were most likely infected prior to arrival in Switzerland. Sub-Saharan Africans and Southeast Asians were often diagnosed to be HIV-positive after showing suggestive symptoms of infection, while European patients were more often diagnosed in a screening setting. Thirteen patients with indication for antiretroviral therapy were forced to leave Switzerland because they were denied asylum. In response to the increasing migrant population attending the HIV clinic, further qualitative and quantitative research is required to improve understanding of this vulnerable population group and to promote their knowledge of the disease and its prevention.