Published data on the association between MDM2 309 T/G polymorphism and lung cancer risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. A total of eight studies including 6063 cases and 6678 controls were involved in this meta-analysis. Overall, significantly elevated lung cancer risk was associated with GG variant genotype in recessive model when all the eligible studies were pooled into the meta-analysis (OR=1.17; 95% CI=1.02-1.34; P(heterogeneity)=0.06). In the subgroup analysis by ethnicity, significantly increased risks were found among Asians for TG versus TT (OR=1.20; 95% CI=1.05-1.37; P(heterogeneity)=0.30), GG versus TT (OR = 1.34; 95% CI=1.01-1.79; P(heterogeneity)=0.03) and dominant model (OR=1.26; 95% CI=1.11-1.43; P(heterogeneity)=0.14). However, no significant associations were found in both Europeans and Africans for all genetic models. This meta-analysis suggests that the MDM2 309G allele is a low-penetrant risk factor for developing lung cancer in Asians.