The karyotypes of six species of Carnivora (Mungos mungo, Paradoxurus hermaphroditus, Potos flavus, Mustelafuro, Felis serval, and Halichoerus grypus), representative of five different families, were studied and compared. Correspondence between almost all chromosome segments was found, and a presumed ancestral karyotype of Carnivora is proposed. Analogies to human chromosomes are also given, and the results obtained are in excellent agreement with previously published gene mapping data on man and the domestic cat.