Raususetarches sakurai gen. et sp. nov. is described from the late Miocene Koshikawa Formation in Kasuga, Rausu, Shiretoko Peninsula, Hokkaido, Japan based on several specimens found in the same rock, as a new genus and species. This new species belongs to the family Scorpaenidae of Scorpaenoidei in having short, triangular posterior spines of preopercle, two ridges and spines of opercle and the first pterygiophore of the anal fin inclined. This species belongs to the subfamily Setarchinae in having lateral line scales forming grooves and cycloid scales. This new species, however, differs from all other genera of the subfamily in having large triangular spines of preopercle; 14 spines and 13 soft rays of the dorsal fin; three spines and eight soft rays of the anal fin; 19 rays of the pectoral fin; hypurals 1 and 2 fused; and hypurals 3 and 4 are also fused. This is the first fossil species of the subfamily Setarchinae.