PURPOSE: To obtain a resin composition which can give a molding excellent in rigidity and impact resistance by adding aluminum borate whiskers to a resin component comprising a specified PP resin and a specified PE resin.

CONSTITUTION: This resin composition is prepared by adding 5-80 pts.wt. aluminum borate whiskers having a diameter of 0.1-3μm and an aspect ratio of 10-50 to 100 pts.wt. resin component comprising 70-97wt.% highly crystalline PP resin selected between a propylene homopolymer having an isotactic pentad fraction P in the range: ≥2P≥0.955 and a melt flow rate (at 230°C under a load of 2.16kg) of 2-30g/10min and an ethylene/propylene copolymer having an isotactic pentad fraction P in the PP part in the range: 1≥P≥0.955, a melt flow rate of 2-30g/10min and an ethylene content of 0.5-15wt.% and 30-3wt.% PE resin prepared by polymerization in the presence of a catalyst comprising a metallocene compound containing a tetravalent transition metal.