Molecular and taxonomic studies of subterranean termites in the genus Reticulitermes (Isoptera: Rhinotermitidae) have suggested that Reticulitermes speratus kyushuensis Morimoto is the only species that occurs in Korea. However, the specimens studied to date were collected from a limited number of locations, and basic information about the distribution, taxonomy, and molecular characteristics of this genus in Korea is still lacking. In this study, we collected Reticulitermes specimens from 50 sampling sites distributed throughout the country. By comparing the cytochrome oxidase subunit II gene of mitochondrial DNA sequences, we conclude that Reticulitermes speratus is represented by two haplotypes in Korea. In addition, we report the first occurrence of another Reticulitermes species in this country.