Objective To investigate the cell compatibility of polystyrene(PS) plate chemically modified with RGD peptides.Methods PS surfaces were carboxylated by permanganate oxidation in diluted sulfuric acid,and carboxyls were activated with water-soluble carbodiimide to graft with gelatin,collagen and RGD peptides.IR,X-ray photo-electronic spectroscopy (XPS) and dynamic contact angle were used to characterize the surface modification of PS surface.Results XPS results confirmed the existence of nitrogen element from protein molecules and the covalently binding of proteins to PS surfaces.Dynamic contact angle measurement indicated hydrophilicity of PS surfaces was improved obviously after grafting modification.The cell culture results showed that the cell adhesion and proliferation was better on modified surfaces than the initial.Conclusion The cell compatibility of PS surface was great improved after modification with RGD peptides,which would provide a potential strategy to improve the culture of purified endothelial progenitor cells isolated by immunomagnetic beads.