Abstract: Objective:To investigate the inhibitory effects of proanthocyaidins from lotus seedpod（LSPC）on mice B16 melanoma.Methods:The mice were fed with different dosage LSPC continuely for 13d,on the 14thday,all mice were killed, and the inhibition rate of B16 melanoma was calculated.The changes of apoptosis cells in morphology were observed,and the expression of HMB45 and S-100 protein in B16 melanoma were tested by immune histochemistry method.Results:LSPC can inhibit the proliferation of B16 melanoma.The dosage of 120mg/kg·bw shows the most significantly difference in comparison with the control（p＜0.01）.The inhibition rate of B16 melanoma reaches 55.3%,and the cell apoptosis analysis presents a sub- peak.Conclusions:LSPC has the inhibitory effects on the B16 melanoma and the mechanism is to induce the apoptosis.

Key words: lotus seedpod, proanthocyanidins, B16 melanoma, inhibitory effect