Background Variation in prostate cancer incidence between different racial groups has been well documented,for which genetic polymorphisms are hypothesized to be an explanation.We evaluated the association between polymorphisms in the cytochrome P-450 CYP1A1(CYP1A1)and glutathione S-transferase M1(GSTM1)genes and genetic susceptibility to prostate cancer in Chinese men.Methods Two hundred and eight prostate cancer patients and 230 age matched controls were enrolled in this study.All DNA samples from peripheral blood lymphocytes were genotyped for common genetic polymorphisms of the CYP1A1 and GSTM1 genes using the oligonucleotide microarray(DNA chip)technique and the polymorphism results confirmed by sequencing.The different polymorphisms in prostate cancer patients were also analyzed according to age at diagnosis,prostate specific antigen level,cancer stage and grade(Gleason score).Results The prevalence of the GSTM1(0/0)genotype was significantly higher in prostate cancer patients(58.2%)than in controls(41.7%,P＜0.05).Further analysis demonstrated that the prostate cancer patients with a GSTM1(0/0)genotype were younger than those with the GSTM1(+/+)genotype(P=0.024).No significant differences in the frequency distributions of CYP1A1 polymorphisms were observed between prostate cancer patients and controls.Conclusion GSTM1(0/0)gene polymorphism may be linked to prostate cancer risk and early age of onset in Chinese.