Abstract: The oxidized carbon fibers(OCF) were prepared via surface oxidation treatment of carbon fibers(CF) in concentrated H₂SO₄/concentrated HNO₃ blend acid, and then OCF were modified by silane coupling agent γ-methacryloxypropyl trimethoxy silane(KH-570), to obtain the KH-570 grafting modified carbon fibers(KCF), which were subsequently applied to ethylene-vinyl acetate copolymer(EVA) foamed composites. The surface modified characteristics, the structures and properties of carbon fiber/EVA composites were investigated by FTIR, XPS, Raman, FESEM and electronic universal testing machine etc. The result shows that both oxidation and grafting reaction can increase the content of active functional groups and roughness on surface of carbon fiber, which can improve the compatibility between carbon fibers and EVA matrix, leading to improvement on physical properties of carbon fiber/EVA foamed composites. Under the same conditions, the KH-570 grafting modified carbon fiber/EVA foamed composites have superior physical properties.