The results regarding an association between the polymorphism sites in the dopamine D1 receptor gene and schizophrenia compelled us to study the distribution of the polymorphism in Korean schizophrenia and controls. Eighty-eight schizophrenic patients and normal controls were examined by case-control study for distribution of the polymorphism of the dopamine D1 receptor gene in Korean popualtion to minimize the effect of racial differencies in gene frequencies. The frequencies of the B1 and B2 in schizophrenic patients were 0.11 and 9.89, respectively. And 0.10 and 0.90 in normal control. There was no significant differences in the frequencies in the allele B1 and 2 between schizophrenic patients and normal controls. The author present here the evidence of a lack of alleic association between the polymorphism of the dopamine D1 receptor gene and Korean schizophrenic. The assumption that the dopamine D1 receptor gene has genetic role in the development of schizophrenia was not supported by this case-control study.