Proliferation and migration of vascular smooth muscle cells were the common pathological feature of development and progression of atherosclerosis, hypertension and vascular restenosis. Phenotypic modulation of vascular smooth muscle cells was the basis of its proliferation and migration. So, understanding the mechanisms of phenotypic modulation of these cells may be helpful to prevent and treat the diseases mentioned above. This paper will review the influence factors, signal transduction and transcription factors involved in phenotypic modulation of vascular smooth muscle cells.