To provide a polypropylene based resin composition being excellent in the balance of blocking-resistance, rigidity and low temperature impact-resistance and being further excellent in contamination-resistance of a processing machine.

The polypropylene based resin composition contains a polypropylene based copolymer containing 50-95 wt.% of a polymer component (component A) in which a structural unit derived from propylene is a main component, and 5-50 wt.% of a polymer component (component B) of propylene, ethylene and 4 or more C -olefin in which a content (X) of a structural unit derived from propylene is 10X50 wt.%, a content (Y) of a structural unit derived from ethylene is 50Y70 wt.%, and a content (Z) of a structural unit derived from the 4 or more C -olefine is 0Z20 wt.% (provided that the total of X, Y and Z is made to 100 wt.%), and hydrotalcite.