Abstract: ObjectiveTo explorecy to chrome P₄₅₀ 1A1(CYP1A1)and glutathione Stransferase M1(GSTM1)genetic polym orphisms in Miao population of Guizhou.MethodsCYP1A1 and GSTM1 gene polymorphisms among 97 Miao people were studied with polym rase chain reaction(PCR)and polymerase chain reaction restriction fragment length polymorph sm(PCR-RFLP)technique.ResultsThe allele frequency of CYP1A1m1 was 0.195;the geno types of CYP1A1m1 T T,TC and CC were 71.13%,18.56% and 10.31%,respectively.The frequency of GSTM1 null geno type was 69%.ConclusionThe allele frequency of CYP1A1m1 in Miao population was higher than Caucasian,but lower than Chinese Han opoulation.The frequency of GSTM1 null geno type was higher than German,Polish,Japanese and Korean.