Objective To explore the effect of shear stress on proliferation of vascular endothelial cells (ECs) around stent edge. Methods ECs were divided into static group (as control group), gradient shear stress group (ECs in parallel-plate flow chamber (PPFC) with gradient shear stress ) and steady shear stress group (ECs in rectangular PPFC). Two shear stress groups were subjected to 0.566-1.438 Pa and 1.137 Pa for 6h, respectively. The ECs cell cycle in each group was detected by flow cytometry (FCM). Results The amount of ECs entering cell cycle phases of S and G2+M in gradient shear stress group was much more than that in static group and steady shear stress group P( < 0.05), while the amount of ECs in steady shear stress group entering phases of S and 2G+M was significantly less than that in other two groups (P < 0.05).Conclusion Gradient shear stress induces ECs to enter phases of proliferation while the cell cycle phase is inhibited by the steady laminar shear stress. The result suggests that the gradient shear stress caused by planted stent can induce ECs proliferation, which may play an important role in initial hyperplasia in the restenosis process within the stent.