Polypropylene (PP) fiber reinforced concrete is an important composite. In order to improve the mechanical properties of PP fiber reinforced concrete, polyacrylamide (PAM) was grafted onto the PP surface by the UV irradiation to enhance the hydrophilic property of PP in this study. IR spectra showed the existence of carboxylic acid functional groups on the treated PP surface. AFM images depicted that the treated PP surface had the lower height fluctuation, roughness, and had the acicular appearance. Contact angles of the treated PP were reduced in comparison with that of the original PP. All of these experimental results gave the evidences that PAM had been successfully grafted onto the treated PP surface. Furthermore, OM images depicted that the treated PP adhered to cement hydrate products (C-S-H) more tightly than that of the original PP did. We therefore expect that PP grafted with PAM can enhance mechanical properties of PP fiber reinforced concrete.