The leopard, Panthera pardus, is a threatened species in the world. Although there have been high densities of leopard populations in the Korean Peninsula historically, they became extirpated in South Korea by 1970, leaving almost no genetic specimens. The sub-specific classification of Korean leopards remains obscure even though they have been traditionally classified as Panthera pardus orientalis. Therefore, we attempted to do first the genetic study of South Korean leopards using an old hide of a leopard captured in Jirisan, South Korea in the 1930s. DNA was extracted from the old leopard hide and a total 727 bp of mitochondrial DNA, including NADH5 (611 bp) and D-loop (116 bp) regions, was amplified by PCR. The phylogenetic analysis of the sequence in comparison with the sequences of nine leopard subspecies from Genbank showed that the extirpated Korean leopard belonged to the same clade as the Amur leopard (Panthera pardus orientalis) on the phylogenetic tree. This result indicates that the leopard inhabiting South Korea in the past was the same sub-species as the Amur leopard population currently inhabiting the trans-boundary region with Russia, China and North Korea. The results emphasise the importance of conserving the endangered wild Amur leopard population, estimated to be about 60-80 individuals, because this population could be the source for the restoration of leopards in the Korean Peninsula in the future.