OBJECTIVE： To discuss the correlation between multidrug resistance gene （MDR1） polymorphisms and plasma concentration of risperidone， 9-hydroxyrisperidone and total active substance in Han patients with schizophrenia. METHODS： 78 Han inpatients with schizophrenia in Mental Health Institute of Second Xiangya Hospital of Central South University from Dec. 2011 to Jan. 2013 were selected， LC-MS/MS was conducted to determine the plasma concentration of risperidone， 9-hydroxyrisperidone and total active substance， PCR-LDR was adopted to determine the genotyping of C1236T， G2677T and C3435T of patients， and one-way ANOVA was used to detect the correlation between C1236T， G2677T and C3435T polymorphisms and plasma concentration/dose calibration ratio （C/D） value of risperidone， 9-hydroxyrisperidone and total active substance. RESULTS： The average plasma concentrations of risperidone， 9-hydroxyrisperidone and total active substance for 78 patients were （13.58±8.31）， （25.62±15.52） and （39.24±25.76） ng/ml， respectively； the distribution frequencies of C1236T， G2677T and C3435T met the Hardy-Weinberg equilibrium （P＞0.05）； the risperidone C/D value of patients with C12367T CT and TT genotype were higher than those with CC genotype， risperidone and total active substance C/D values of patients with G2677T TT genotype were higher than those with GG genotype， the differences were statistically significant （P＜0.05）； while there were no significant differences in analyte C/D values in other patients （P＞0.05）. CONCLUSIONS： The MDR1 C1236T and G2677T polymorphisms are associated with plasma concentration of risperidone and total active substance in Han patients with schizophrenia.