Objective：To clarify the effect of substrate stiffness on the growth and biological activity of human umbilical vein endothe－lial cells（HUVECs） through studying the mechanical properties of substrate for cell growth and inoculating HUVECs to substrates with different stiffness. Methods：Substrates with different stiffness were built by using bisacrylamide and acrylamide compounds. The sub－strates were sterilized and were cross-linked by collagen to inoculate HUVECs. MTT assay，phalloidin cell staining and flow cytometry analysis were performed to detect the cell cycle. Results：With the enhancement of base stiffness，the proliferation of HUVECs was inhibited significantly（P<0.01） and the cell morphology and growth cycle were also changed accordingly. Conclusions：The changes in substrate stiffness have great impact on the growth and proliferation of HUVECs，which gives further biomechanical evidence to ex－plain the atherosclerotic vascular endothelial cell morphology and dysfunction.