Background: Many studies have investigated the association between glutathione S-transferase T 1 (GSTT1) null genotype and risk of prostate cancer, but the impact of GSTT1 null genotype in Asians is still unclear owing to inconsistencies across results. Thie present meta-analysis aimed to quantify the strength of the association between GSTT1 null genotype and risk of prostate cancer. Methods: We searched the PubMed, Embase and Wangfang databases for studies of associations between the GSTT1 null genotype and risk of prostate cancer in Asians and estimated summary odds ratio (OR) with their 95% confidence interval (95% CI). Results: A total of 11 case-control studies with 3,118 subjects were included in this meta-analysis, which showed the GSTT1 null genotype to be significantly associated with increased risk of prostate cancer in Asians (random-effects OR = 1.49, 95% CI 1.15-1.92, P = 0.002), also after adjustment for heterogeneity (fixed-effects OR = 1.45, 95% CI 1.23-1.70, P < 0.001). No evidence of publication bias was observed. Conclusions: This meta-analysis of available data suggested the GSTT1 null genotype does contribute to increased risk of prostate cancer in Asians.