In a series of genetic studies of the Korean population, the carbonic anhydrase polymorphism was investigated from unrelated 1,100 Korean individuals. The allele frequencies of carbonic anhydrase I and II (CA I and CA II) were analyzyed from the red blood cell by the method of starch gel electrophoresis (Hopkinson et al., 1974). The electrophoretic phenotypes of CA I was monomorphic and two electrophoretic phenotypes, CA II I-1 and CA II 1-2, were observed as the products of the different combinations of two alleles, CAII*1 and CA II*2 at autosomal loci. Based on the investigation of 1,100 samples, the following gene frequencies were obtained; frequencies of CA II*1 and CA II*2 were 0.999 and 0.001, respectively, and the CA I*1 was only allele found in Korean population.