Objective To study AngⅡ induced apoptosis of HUVECs and to observe the protective effect of serum contained huangqi on endothelial cell.Methods ECV-304 cells were randomly divided into control group,AngⅡgroup and huangqi group.In the control group,cells were cultured for 18 h,and the concentration of AngⅡ were 0 mol/L,1×10-6 mol/L,1×10-5 mol/L and 1×10-4 mol/L.The cell proliferation was measured by MTT assay.Electron microscope was used to observe the change of HU-VECs.Ultrastructure of HUVECs induced by AngⅡ was observed by electron microscope.In the huangqi group,serum contained huangqi of different concentration were added into the medium and cultured for 24 h,then AngⅡ of 1×10-4 mol/L was included and cultured for 18 h,and the apoptosis ratio induced by AngⅡwas measured by flow cytometry.Results AngⅡof different con-centration could all significantly inhibit HUVECs proliferation.AngⅡof different concentration could all induce endothelial cell ap-optosis.HUVECs apoptosis was observed by electron microscope.HUVECs apoptosis induced by AngⅡcould be inhibited by ser-um contained huangqi.Conclusion Serum contained huangqi could protect endothelial cells.