Abstract: Objective To assess the association between metabolic syndrome and risk of endometrial cancer. Methods We searched references from CBM、CNKI、Wangfang、PubMed、Web of Science and Cochrane Library before October 2014 to select articles on the association between metabolic syndrome and risk of endometrial cancer which met initial criteria. Two evaluators independently reviewed and selected articles based on predetermined selection criteria and assessed articles with Newcastle-Ottawa Quality Scale. Stata 12.0 was used to conduct meta-analysis. Q test and I² were used to conduct heterogeneity test. Results A total of 5 studies were included in the final analyses, involving 428 665 participants and 3 112 cases of endometrial cancer. Metabolic syndrome was associated with an increased risk of endometrial cancer RR=1.96, 95%CI(1.32,2.89), P=0.001, with significant heterogeneity among studies (I²=94%, P=0.000), so results were summarized by random effects meta-analysis,but no indication for publication bias in the Egger’s test (P=0.240). A sensitivity analysis omitting two studies produced no heterogeneity (I²=14.2%, P=0.312). The risk estimates for any single factor of the syndrome were 1.86(P<0.001) for higher values of body mass index and/or waist, 1.81(P=0.044) for hyperglycemia, 1.81 (P=0.024) for higher blood pressure values, and 1.17 (P<0.001) for high triglyceride levels; there was no significant association with low HDL-cholesterol (P=0.259). Conclusions Metabolic syndrome is associated with an increased risk of endometrial cancer;among the components of the syndrome, obesity/high waist is more strongly associated with endometrial cancer.