A polypropylene-based resin composition comprising 61 to 85% by weight of a copolymer (X) of propylene, α-olefin having 4 or more of carbon atoms and/or ethylene, in which a content of a constitutional unit derived from propylene is 86 to 97% by weight, a total of a content of a constitutional unit derived from ethylene and a content of a constitutional unit derived from α-olefin having 4 or more of carbon atoms is 3 to 14% by weight, provided that a total of the content of a constitutional unit derived from propylene, the content of a constitutional unit derived from ethylene and the content of a constitutional unit derived from α-olefin having 4 or more of carbon atoms is defined to be 100% by weight, 1 to 38% by weight of a copolymer (Y) of propylene and α-olefin having 4 or more of carbon atoms, in which a melting point is 115° C. or more, and a content of a constitutional unit derived from α-olefin having 4 or more of carbon atoms is 10 to 30% by weight, and 1 to 38% by weight of a copolymer (Z) of propylene and α-olefin having 4 or more of carbon atoms, in which a melting point is less than 115° C., and a content of a constitutional unit derived from α-olefin having 4 or more of carbon atoms is 30 to 40% by weight, wherein a total of the copolymer (X), the copolymer (Y) and the copolymer (Z) is defined to be 100% by weight.