Public health aspects concerning health and health-care of unregistered migrants have been rarely investigated. This article aims at providing some empirical data which are derived from the documentation and annual reports of two health-care institutions specialised in health-care for unregistered migrants in Germany and Italy taking into account the different legal regulations between Germany and Italy for the health-care of irregular migrants. The data show that the patients in both institutions are rather young and immigrated often from East Europe and the former Soviet Union. Their main diseases did not differ much from the average spectrum except for showing a higher prevalence of "poverty-related illnesses" like infectious and skin diseases.