Objectives:The aim of this study is to evaluate the association between antipsychotics-induced weight gain and the polymorphisms in the dopamine receptor D2(DRD2) genes. Methods:We measured the weight and height of 125 schizophrenia patients before and after treatment. The genotyping for rs1800497 was performed using TaqMan single nucleotide polymorphism(SNP) genotyping assay. Results:There was a significant difference in the amisulpride-induced change of body mass index(BMI) according to the frequency of rs1800497 genotype. Conclusion:This is the first positive association study between DRD2 gene and the amisulpride induced weight gain in Korean schizophrenia patients. A larger scale research on more SNP of the DRD2 gene will make a progress in the study of amisulpride induced weight gain.