A polypropylene resin composition contains 2 to 15 wt % of a moldability improver (A) and 85 to 98 wt % of a polypropylene resin (B). The moldability improver (A) is formed of propylene block copolymers (A-1) and (A-2). Each of the propylene block copolymers (A-1) and (A-2) has a crystalline propylene polymer component (A-11), (A-21) and a propylene-ethylene random copolymer component (A-12), (A-22). The propylene block copolymer (A-1) is characterized in that the melt flow rate of the crystalline propylene polymer component (A-11) is high, whereas the propylene block copolymer (A-2) is characterized in that the content ratio of the propylene-ethylene random copolymer component (A-22) is high. The polypropylene resin (B) is formed of a propylene-ethylene block copolymer (B-1), at least one of an ethylene elastomer and a styrene elastomer (B-2) and an inorganic filler (B-3).