In this study, the weight loss efficacy and security of Momordica charantia extracts was investigated.By the experiment of percutaneous absorption, promoting lipolysis and inhibiting fatty acid synthase, the weight loss efficacy of Momordica charantia extracts were evaluated; By red blood cell hemolysis test, chicken embryo chorioallantoic membrane experiment and patch test, the security of Momordica charantia extracts were evaluated. The results showed that, Momordica charantia extracts has the efficiency of weight reduction, and has no stimulation at low concentration -lower than 100mg/mL-, thus,it can be used as a kind of topical additive with weight-loss efficacy.