The Morphological characteristics of four species of Korean Abalone species, Haliotis discus hannai, H. discus discus, H. gigantea, H. madaka were compared. then Phenotypic traits were characterized. we collected from coast of samchonpo, sacjon-si, Gyeongsangnam-do and jeju-do of korea 69 individual of Haliotis discus hannai from 2013 December to 2014 January, 180 individual of H. discus, 72 individual of H. gigantea and 54 individual of H. madaka respectively then morphological traits of theses species characteristics were compared. The relationship between Shell length (SL), shell breth (SB), shell height (SH) and total weigh (TW) was expressed by the following equation: SB = 0.6346SL + 3.9082 (R2 = 0.8956), SH = 0.2399SL + 3.2609 (R2 = 0.8024), TW = 0.0009SL2.5622 (R2 = 0.8088) in the Haliotis discus hannai, SB = 0.7249SL + 1.8035 (R2 = 0.9634), SH = 0.3115SL ? 11.223 (R2 = 0.8593), TW = 0.0001SL2.9696 (R2 = 0.8956) in the H. discus discus, SB = 0.7730SL ? 1.1931 (R2 = 0.933), SH = 0.2082SL + 3.2627 (R2 = 0.6927), TW = 0.0002SL2.8330 (R2 = 0.8431) in the Haliotis gigantea, SB = 0.7513SL ? 1.0951 (R2 = 0.913), SH = 0.2618SL ? 6.1538 (R2 = 0.6927), TW = 0.0001SL2.9614 (R2 = 0.9353) in the Haliotis madaka.