Ecological character displacement is phenotypic divergence driven by resource competitions. Until now many studies about ecological character displacement have reported in various taxa (e.g. Galapagos finche, Threespine stickleback, Anolis lizard etc.). However these studies mainly focused on phenotypic divergence driven by intra generic competition. Because competition can occur among distantly related species, ecological character displacement may occur by inter generic competition. Amami tip-nosed frog which is endangered and endemic in Amami island and Tokunoshima island. This frog coexists with non-congeneric potential competitor Otton frog in Amami island while the frog is released from the potential competitor in Tokunoshima island. Therefore these islands provide excellent opportunity to examine inter generic ecological character displacement. Here, we examined the prediction following the criteria in Schluter (2000) (phenotypic divergence of Amami tip-nosed frog between these islands, changes in phenotype match ecological shift of prey preference of Amami tip-nosed frog between these islands, similarity of potential prey availability between these islands, similarity of prey preference between these species). We will discuss the possibility of inter generic ecological character displacement in Amami tip-nosed frog.