These studies were conducted to compare the radulae of six species (Nordotis madaka, N. gigantea, N. discus discus, N. discus hannai, Sulculus diversicolor diversicolor, and S. diversicolor supertexta) of the family Haliotidae in Korea using the scanning electron microscope. As a result, teeth of all species has asymmetry rhipidoglossate form and basic tooth formula of six Haliotids was £¾50-5-1-5-50£¼ (one central tooth, five lateral teeth, and over the 50 marginal teeth on each side). Therefore it is difficult that all of the species can be detected sharply the difference of interspecies by comparisons of radulae.