Opposite to many other ichthyological areas discussed in this volume, those of Lower Guinea and Central Africa remain poorly known. An important part of this region has not been yet explored due to its inaccessibility, but also due to the political situation in the countries located in the area. 24 families of primary freshwater (including the Grasseichthyidae) with 102 genera and 392 species are presently known from Lower Guinea. Cyprinidae and Cyprinodontidae show the highest species diversity. In Central Africa, 26 families (including the Grasseichthyidae) with 696 species are known. Cyprinidae, Mormyridae and Cichlidae show the highest specific diversity. Opposite to West Africa, the limited information available for Lower Guinea and Central Africa does not enable at present to propose ecological and evolutive hypotheses to explain this important diversity, its origin and dispersion. However, this poorly known and forgotten central African region deserves much more ichthyological interest as it contains one of the most important ichthyological communities of the world.