Abstract: Objective To observe the effect of connective tissue growth factor(CTGF) on expression of matrix metalloproteinase-2(MMP-2) and MMP-9 in vascular endothelial cells(VSMC). Methods Primary VSMC were cultured and identified with immunohistochemical staining.CTGF483-siRNA was transfected into VSMC with liposome.Expression of CTGF,MMP-2 and MMP-9 in VSMC were detected by Western blot. Results Immunohistochemical staining showed positive reaction in VSMC which were specifically stained.The expression levels of CTGF,MMP-2 and MMP-9 were significantly lower in VSMC after transfection than before transfection(P<0.05). Conclusion Down-regulation of CTGF expression can inhibit the expression of MMP-2 and MMP-9 in VSMC of rats,effectively,delay the development of atherosclerosis,and thus may become a new target for the prevention and treatment of carotid atherosclerotic ischemic cerebral vascular disease.