Objective To explore the biological influence of shear stress on intact artery. Methods The common carotid arteries of pigs were cultured with a new artery organ-culture system under shear stress in vitro. 100mmHg of pressure and stable flow were selected. After 1, 4 and 7 day, immunohistochemistry was performed on the sections of artery with antibody to antigen BrdU. Apoptosis were identified by morphology, TUNEL and Hoechst 33258 staining. Results The results showed that the proliferation rate of vascular smooth muscle cells (VSMC) increased continuely while the apoptosis rate increased at first and then decreased under low shear stress, maximum on day 1. Conclusion These results suggest that proliferation and apoptosis of VSMC have important effects on vascular remodeling under low shear stress; Unbalance of proliferation and apoptosis may be one of foundations of cardiovascular diseases.