Objective: To investigate the changes in phenotype and function of vascular smooth muscle cells (VSMCs) from varicose great saphenous vein. Methods: Thirty specimens of varicose great saphenous vein (varicose group) and 15 specimens of normal great saphenous vein (normal group) were collected, and the VSMCs in the two groups of specimens were isolated and cultured. In the two groups of VSMCs, the proliferation, migration, adhesion and aging status and cytoskeletal protein expression, as well as the expressions of apoptosis associated factors and extracellular matrix metabolism associated factors were determined. Results: In VSMCs of varicose group compared with VSMCs of normal group, the expression of cytoskeletal protein F-actin was increased; the proliferative ability and numbers of migrating, adhering, and aging cells were significantly increased (all P<0.05); the mRNA and protein expressions of pro-apoptotic factor Bas and apoptotic executioner caspase-3 were significantly decreased, while mRNA and protein expressions of anti-apoptotic factor Bcl-2 was significantly increased (all P<0.05); the mRNA and protein expressions of matrix metalloproteinases (MMP-2 and MMP-9) and matrix metalloproteinase inhibitors (TIMP-1 and TIMP-1) were significantly increased (all P<0.05). Conclusion: VSMCs from varicose great saphenous vein feature evident dedifferentiation and demonstrate increased proliferative and synthetic capacity. These phenotypic and functional abnormalities in VSMCs may be one of the pathogeneses for varicosity.