This study investigated the effect on cell adhesion of surface modifications of polystyrene(PS) by chemical and biological factors. To improve cell adhesion of polystyrene with fibroblast was firstly allowed to generate peroxide groups by argon plasma treatment. Then polystyrene graft polymerized using allylamine(PS-g-AA). The effect of surface amine group concentration on the extent of collagen(Col) immobilization was investigated. Collagen was then covalently immobilized through amide bonds between the residue amine groups and carboxylic ones in the presence of carbodiimide(PS-g-AA/Col). The surface of the grafted polystyrene was studied by Fourier transform infrared spectroscopy-attenuated total reflectance(FTIR-ATR) X-ray photoelectron spectroscopy(ESCA), and contact angle goniometry. The XPS survey scan as well as carbon 1s(C1s), and nitrogen 1s(N1s) core spectra of the modified surfaces, confirmed the changes in chemical composition of the PS surface due to graft moieties. The PS, PS-g-AA, and PS-g-AA/Col were evaluated by measuring the water contact angle of the samples. Decrease in the contact angel was observed with graft polymerization. Surface tension of the scaffolds increased to 50.95 mJ/cm2 due to the grafting of AA and collagen. The adhesion of fibroblast on the surface of the samples was examined by the cell adhesion assay, and the adherent cells were observed by phase contrast microscopy and scanning electron microscopy(SEM). Fibroblast cultured on the PS-g-AA, PS-g-AA/Col substrates showed significantly improved adhesion and expansion compared to PS substrates.