Two population groups in South Korea, one from Kwangju and one from Kangreung, were studied in regard to the erythrocyte enzyme polymorphisms GPT, ACP, GLO, ESD, 6PGD, ADA, AK, PGP and subtypes of PGM1 as well as regarding the serum protein variants of C3, HP, BF, PLG, AMY and the subtypes of GC, TF and PI. The results were compared with data of the population groups from the area of Cheju Island, Taejon and Seoul. The Korean population showed a rather high degree of genetic homogeneity.