By means of the squash technique of the intestinal epithelium, the karyotypes ofRana sauteri and Rana latouchii from Taiwan are investigated. These two species, like many other members of the genus Rana, show 26 chromosomes which consist of 5 large-sized pairs and 8 small-sized pairs. The chromosome morphology of the large pairs is similar to that of the other common Rana species, leaving the small pairs which show a characteristic feature in respective species. The morphology of 2 small pairs of R. sauteri is different from that of any other Taiwan and Japanese ranids. Based on genotypic and phenotypic evidence we suppose that R. sauteri could be an intermediate type of the brown-frog group and the genus Amalops. The chromosomes ofRana latouchii are also dissimilar to those of typical brown frogs in Japan. Evidence presented here corresponds to the results of the external morphology in both larval and adult individuals of this species.