OBJECTIVE： To investigate the effects of UGT1A6 and UGT1A9 gene polymorphisms on blood concentration  of valproic acid in Han epileptic patients. METHODS： Totally 107 Chinese Han epileptic patients were selected from outpatient department of our hospital during Jan. 2014-Apr. 2015. They were given valproic acid monotherapy treatment for 3 months to 6 years. The steady state concentration of valproic acid was detected by EMIT. UGT1A6 （rs2070959， rs6759892） and UGT1A9 （rs13418420， rs2741045， rs2741049， rs6731242， rs72551330） genotypes were detected by MALDI-TOF-MS. The correlation of gene polymorphism with concentration dose ratios （CDR） of valproic acid was investigated. RESULTS： UGT1A9 rs72551330 mutation had not been detected， and the frequency of genotypes in other 6 sites were all in line with Hardy-Weinberg balance （P＞0.05）. The CDR of valproic acid in patients with UGT1A6 rs2070959， rs6759892 mutation （AG+GG or TG+GG type） were significantly lower than those with wild homozygote （AA or TT type）， with statistical significance （P＜0.05）. There was no statistical significance in CDR of valproic acid among patients with UGT1A9 rs13418420， rs2741045， rs2741049 and rs6731242 wild homozygote and mutation （P＞0.05）. CONCLUSIONS： UGT1A6 rs2070959， rs6759892 gene polymorphisms of Han epileptic patients are associated with blood concentration of valproic acid， and the patients with UGT1A6 rs2070959， rs6759892 mutation need more dose of valproic acid.