Direct examinations of blood and serologic tests were used to assess the intensity of the filarial endemicity in Gabon. Both methods revealed that the prevalence of filariasis with microfilaremia (Loa loa and Dipetalonema perstans) is presently very elevated. The areas that are more involved are the forest regions as well as the highest ones (ogoue, Lolo, Ngounie). Women appeared to be suffering from loasis to a lesser extent than men. On the other hand, the prevalence was identical for Dipetalonema perstans. For the gabonese population one can approximately say that 3 out of 5 adults patients have filariasis, two being D. perstans and one L. loa. Consequently these affections represent a major public health problem. Finally one must note that no case of lymphatic filariasis has been identified.