This invention provides polypropylene resin compositions which have sharply improved balance of physical properties in comparison with the related polypropylene materials, are materials that can be used in both interior and exterior parts of automobiles, have excellent thin-wall moldability and can sharply reduce generation of flow marks. Particularly, it provides a polypropylene resin composition which comprises specified amounts of (A) a specified ethylene-propylene block copolymer, (B) a specified thermoplastic elastomer and (C) talc, wherein it has specified values of physical properties measured by ASTM and has a degree of b-axis orientation of 720 or more which is calculated from the ratio of differential peak intensities measured by wide-angle X-ray diffraction of the central area of an ASTM No. 1 dumbbell prepared by injection molding.