During the past decade, a number of studies were published to evaluate the association between murine double minute 2 (MDM2) T309G polymorphism and risk of liver cancer. However, the association between MDM2 T309G polymorphism and risk of liver cancer was still unclear owing to the conflicting results from those published studies. An undated meta-analysis of all eligible studies was carried out to comprehensively assess the association. The pooled odds ratio (OR) with 95 % confidence interval (95% CI) was used to evaluate the association between MDM2 T309G polymorphism and risk of liver cancer. Finally, ten studies with a total of 2,243 cases and 3,471 controls were finally included into the meta-analysis. Overall, there was an association between MDM2 T309G polymorphism and risk of liver cancer (G vs. T: OR=1.39, 95% CI 1.17-1.64, P<0.001; GG vs. TT: OR=1.87, 95% CI 1.34-2.62, P<0.001; GG/GT vs. TT: OR=1.61, 95 % CI 1.24-2.08, P<0.001). Subgroup analysis in Europeans showed that there was also an association between MDM2 T309G polymorphism and risk of liver cancer in Europeans (G vs. T: OR=1.81, 95% CI 1.45-2.27, P<0.001; GG vs. TT: OR=3.26, 95% CI 1.99-5.32, P<0.001; GG/GT vs. TT: OR=2.20, 95% CI 1.58-3.07, P<0.001). Subgroup analysis in Asians showed that there was also an association between MDM2 T309G polymorphism and risk of liver cancer in Asians (G vs. T: OR=1.27, 95% CI 1.06-1.52, P=0.010; GG vs. TT: OR=1.59, 95% CI 1.11-2.27, P=0.011; GG/GT vs. TT: OR=1.41, 95% CI 1.07-1.87, P=0.016). The meta-analysis provides a strong evidence for the association between MDM2 T309G polymorphism and risk of liver cancer.