Abstract: A reformed polypropylene resin composition having high degree of fluidity and excellent impact strength and rigidity, and further having a melt flow rate of from 50 to 150 g/10 min. and establishing a relationship between the melt flow rate (X) and the Izod impact strength (Y) which satisfies a relation Y.gtoreq.-4.7878 log X+13.8829. The reformed polypropylene resin composition is obtained by blending 0.01 to 0.2 parts by weight of an organic peroxide and 0.05 to 1 part by weight of a crosslinking agent per 100 parts by weight of a total of 50 to 90 parts by weight of a polypropylene having a melt flow rate at 230.degree. C. of 10 to 70 g/10 min, 0 to 25 parts by weight of an olefin copolymer rubber, and 5 to 40 parts by weight of an organic filler, and by melt-kneading the mixture by using a biaxial extruder maintaining a temperature of 120.degree. to 200.degree. in the preceding stage of the screw and a temperature of 180.degree. to 270.degree. C.