Uncinaria spp. parasites were collected from two Tsushima leopard cats found on Tsushima Island, Nagasaki prefecture, Japan. One Uncinaria sp. was observed in the large intestines, and the other was observed in the small intestines. The nematode found in the large intestines was determined to be Uncinaria felidis by morphological identification. The other Uncinaria sp. found in the small intestines was morphologically different from U. felidis in the short-length of prevulvar flap. After isolation of genomic DNA of these worms, a second internal transcribed spacer (ITS2) of ribosomal DNA was amplified and sequenced using PCR techniques. The ITS2 region of U. felidis had 222 nucleotide sequences in length. The alignments of ITS2 sequence for Uncinaria felidis and Uncinaria sp. showed one nucleotide (0.45 %) replacement. These differrences may be regarded as intraspecific variation.