Objective:To abserve the effect of rapamycin on the proliferation of human umbilical vein endothelial celI(HUVEC)in vitro.Methods:HUVEC were exposed to different concentrations of rapamycin (0.1ng/ml-20ng/ml) solution,and the influence of rapamycin on cell proliferation induced by VEGF was investigated by MTT assaying method.Results:Various concentrations rapamycin inhibited cell proliferation.Conclusion:rapamycin had the concentration dependent inhibitory effect in HUVEC.The mechanism of rapamycin on neovascularization is to inhibit the proliferation of HUVEC.