A recent taxonomic study revealed that the name Rana okinavana Boettger, 1895 is a subjective senior synonym of R. psaltes Kuramoto, 1985 from the Yaeyama Island Group of the Southern Ryukyus and Taiwan. This led the brown frog of the genus Rana from the Okinawa and the Amami Island Groups of the Central Ryukyus, long been referred to as R. okinavana in various fields of zoology, to be unnamed. Moreover, molecular phylogenetic analyses revealed that the brown frogs from the Okinawa and the Amami Groups are so divergent genetically as to be recognized as two distinct species. Because there are no available names for these brown frogs, I describe the populations from the Okinawa and the Amami Groups as two new species, R. ulma and R. kobai, respectively.