54 species of ammonites occurring in the Cretaceous deposits of South-West Crimea are described and figured. The stratigraphical scheme of the Lower Cretaceous deposits, particularly the Berriasian and Valanginian stages, is revised according to the new finds of ammonites. The section of the Lower Valanginian is given in details, as well as a total section of the Cretaceous deposits in the River Belbek Basin.