Objective To investigate the effect of fenofibrate on the matrix metalloprotenase-9 (MMP-9) expression and the proliferation of cultured human umbilical vein endothelial cell (HUVECs) induced by oxidized low density lipoprotein(ox-LDL-C).Methods HUVECs cultured in vitro at passage 4 to 9 were used for the experiment.They were divided into control group,ox-LDL-C group (100 mg/L) and ox-LDL-C + fenofibrate group.The cells in ox-LDL-C + fenofibrate group were firstly incubated with 10,50,100 μmol/L fenofibrate respectively for 6 h,then incubated with 100 mg/L ox-LDL-C for another 24 h.MMP-9 expression in supernatant medium was detected by enzyme-linked immuno sorbent assay (ELISA) and cell proliferation was measured by MTT assay.Results Compared with the control group,ox-LDL-C (100 mg/L) could inhibit the proliferation of HUVECs (P ＜ 0.01) and promote the production of MMP-9 of HUVECs.Fenofibrate could inhibit the proliferation of HUVECs induced by ox-LDL-C in a dose-dependent manner (P ＜ 0.01).Fenofibrate (10,50,100 μmol/L) could significantly stimulate the production of MMP-9 of HUVECs induced by ox-LDL-C (P ＜ 0.01).The stimulation effect was dose-dependent.Conclusion Fenofibrate can inhibit the production of MMP-9 in HUVECs induced by ox-LDL-C,promote the proliferation of HUVECs and protect endothelial function in a dose-dependent manner,then may play the role of anti-artherosclerosis besides lipid regulation.