In this study, a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)-based method for species identification was applied to eight Japanese Lymantria species, including the four "Asian gypsy moth" species [Lymantria dispar japonica (Motschulsky), Lymantria umbrosa (Butler), Lymantria albescens Hori and Umeno, and Lymantria postalba Inoue] and four other species [Lymantria xylina Swinhoe, Lymantria mathura Moore, Lymantria monacha (Linnaeus), and Lymantria lucescens (Butler)]. We sequenced the second internal transcribed spacer (ITS2) region of nuclear ribosomal DNA (rDNA) of one individual from each of the eight species. We analyzed the recognition sites of a restriction endonuclease (MnlI) to identify the Lymantria species by PCR-RFLP. We then applied PCR-RFLP analysis to 330 individuals from 54 populations of the 8 species. As a result, these species could be correctly identified with the exception of two species pairs (L. dispar japonica and L. umbrosa; L. albescens and L. postalba). These results suggest that this PCR-RFLP method based on the ITS2 region is useful for identifying Japanese Lymantria species.