Using mitochondrial DNA sequences, we surveyed genetic features of 12 individuals of Cynops pyrrhogaster introduced into Hachijojima Island, in order to estimate their possible origin in the main islands of Japan. The phylogenetic analysis revealed that the 12 examined newts of the introduced population display no genetic diversity and share characteristics with the conspecific population of Shikoku and thus belong to the WESTERN Clade proposed by earlier studies. Our results suggest that the Hachijojima population, having experienced a drastic founder effect, stems from very few individuals from the Shikoku District approximately 650 km to the west.