ObjectiveTo systematically review the relationship between T309G polymorphism of murine double minute 2 (MDM2) gene and susceptibility of prostate cancer. MethodsThe PubMed, Embase, WanFang Data, CNKI databases were electronically searched to collect case-control studies related to the objectives from inception to May, 2023. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. Meta-analysis was then performed by using Stata 14.0 software. ResultsA total of 10 studies involving 5 781 patients and 5 477 healthy controls were included. The results of meta-analysis showed that the MDM2 gene T309G polymorphism was not associated with preeclampsia (allele model G vs. T: OR=0.89, 95%CI 0.77 to 1.04, P=0.13; homozygote model GG vs. TT: OR=0.86, 95%CI 0.64 to 1.16, P=0.32; heterozygote model TG vs. TT: OR=1.04, 95%CI 0.86 to 1.26, P=0.12; dominant model GG+TG vs. TT: OR=0.96, 95%CI 0.89 to 1.04, P=0.36; recessive model GG vs. TG+TT: OR=0.84, 95%CI 0.63 to 1.14, P=0.27). The results of subgroup analysis based on ethnicity and source of control were similar to the overall results. Sensitivity analysis showed that the results were robust. Conclusion Current evidence shows that the MDM2 gene T309G polymorphism is not associated with prostate cancer susceptibility. Due to the limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.