Glutathione S-transferase P1 (GSTP1) is an important phase II enzyme involved in the metabolism of xenobiotics and whose polymorphisms have been related to individual cancer risks. The objective of this study was to explore the association of GSTP1 A1578G (Ile105Val) polymorphism with susceptibility and clinicopathologic characteristics of bladder cancer in a Chinese population.We investigated the distribution of GSTP1 A1578G polymorphism in 200 bladder cancer patients and in 200 age- and sex-matched cancer-free controls. The polymorphisms were analyzed using polymerase chain reaction-restriction fragment length polymorphism assay. Genotype and allele frequencies and their associations with demographic factors, smoking status, stage, grade, and histological type of bladder cancer were investigated.The prevalence of GSTP1 GG genotype in cases was 22.5%, compared with 13.5% in the control group (odds ratio = 1.86, 95% confidence interval = 1.10-3.14, p = 0.02). There was an association between smoking status and bladder cancer (odds ratio = 1.77, 95% confidence interval = 1.17-2.67, p = 0.007). When stratifying by the stage, grade, and histological type of bladder cancer, we found no statistical association.These data seem to indicate that the GSTP1 GG genotype is associated with a modest increase in the risk of bladder cancer in a Chinese population.