To investigate the suppressive effect of Icaritin on angiogenesis of human umbilical vein endothelial cells (HUVEC) and its associated mechanisms.Methods：HUVEC cells were cultured in vitro， and we observed the effects of Icaritin on its proliferation， migration and tube formation.The content of vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) was detected by ELISA.Results：Icaritin had no significant effect on the proliferation of HUVEC cells after 48h treatment.The number of migrated cells in Icaritin high concentration group (ICT1 10-6 mol/l)， middle concentration group (ICT2 10-7 mol/l)， low concentration group (ICT3 10-8 mol/l) and Thalidomide (TLD) group were 4.67±1.26， 10.48±3.15， 21.06±6.83， 19.15±6.03 respectively， and all of which were lower compared with the control group (41.38±7.78) (P<0.01).The area of tube formation in ICT1、ICT2、ICT3 and TLD were separately 5 867.45±925.36， 1 627.33±288.56， 735.73±325.65， 2 933.24±741.43 μm2 per vision， all of which were lower than the control group (7 883.69±1 034.85 μm2 per vision) (P<0.01).After Icaritin treatment， HUVEC cells had a significant lower ability to secret VEGF， but asfor PEDF， it was on the opposite situation.Conclusion：Icaritin can inhibit the angiogenesis of HUVEC cells in vitro.Such effect may be related to the decreased activity and synthesis of VEGF in vascular endothelial cells， and also associated with the increased activity and synthesis of PEDF.