Vitiligo is an acquired depigmentation disorder, and reactive oxygen species have an important role in the physiology of cell damage. Reduced catalase enzyme activity and accumulation of excessive hydrogen peroxide have been observed in vitiligo. In a hospital-based case-control study of vitiligo patients (n=749) and age- and sex-matched healthy controls (n=763), we investigated three catalase (CAT) gene polymorphisms (-89A>T, 389C>T, and 419C>T) to examine whether CAT gene polymorphisms are associated with vitiligo susceptibility in the Chinese population. The case-control analysis revealed a 1.54-fold (95% confidence interval (CI) 1.25-1.91) increased risk of developing vitiligo for -89A>T genotype carriers. No evidence for any association between 389C>T and 419C>T polymorphisms in the catalase gene and vitiligo susceptibility was found. An analysis of haplotypes showed increased risk for T(-89)C(389) (odds ratio (OR) 1.90, 95% CI 1.26-2.86) and T(-89)T(389) (OR 2.80, 95% CI 1.24-6.30). Logistic regression analysis of catalase activity also showed a dose-response relationship between increased risk and decreased activity in CAT -89A>T variant genotype carriers, especially in vitiligo patients (P(trend) <0.001). Our molecular epidemiologic findings suggest that the CAT -89A>T variant genotypes were associated with a significant decrease in catalase enzyme activity and a genetic predisposition for vitiligo in Chinese people.