In this paper a revision of the genus Castillomys Michaux, 1969 is given. Previously described subspecies are elevated to species rank, and a new species, Castillomys rivas, is proposed. Several populations from Italy and Turkey are transferred to the genus Centralomys de Giuli, 1989. For a population from Maritsa the new subgenus Rhodomys is created within the genus Occitanomys.