The immunodepression, related or not to AIDS, induces the emergence of opportunistic parasitosis and mycosis. Our objective is to analyze these pathogenic agents, their clinical expression and gravity in immunocompromised individuals. Our retrospective 9 years study reported parasitic and fungic infections complicating immunodepression. Among 31 HIV infected patients, we diagnosed the following parasitosis: Cryptosporidium (7 cases), Isospora belli (2 cases) and Enterocytozoon bieneusi (1 case). Pulmonary pneumocystosis was diagnosed in 6 cases, cerebral toxoplasmosis in 6 cases and meningo-cerebral cryptococcosis in 1 case. The systemic candidasis was diagnosed in 13 leukaemic patients. The intestinal anguilluliasis was found in 5 patients treated with corticoïds for long periods. A case of Kala azar was observed in a 83 years man treated with corticoïds. A disseminated aspergillosis occurred in a child with a Chediack Higashi syndrome. A gingivo-labial fusariosis was diagnosed in a leukaemic patient. This emergency of the new parasitic and fungal agents requires a better understanding of these affections in order to improve their early diagnosis and treatments.