Abstract: Obesity or overweight had become a serious epidemic problem in modern society and was one of the risk factors for many metabolic diseases such as diabetes and lipid metabolism disorders. Animal experiment was an important part of preclinical studies and are good method for researching disease,pharmacological. The aim of this study was to investigate the effects of medium chain triglyceride(MCT)on body weight in rats and mice. Three databases,PUBMED,EMBASE and WEB of SCIENCE were searched,the effect of medium chain triglycerides or coconut oil diets in rat and mice with long chain triglyceride diets were compared and analyzed. The data was expressed as normalized mean difference(SMD)or weighted mean difference(WMD)and 95% confidence interval(CI). Overall,the intervention of medium chain triglycerides could reduce the body weight of rat(SMD,-0.76(95%CI:-1.16,-0.37))or mice(WMD,-1.39(95%CI:-2.23,-0.54)). The intervention of medium chain triglycerides has a certain effect on reducing body weight.