The present invention provides a flame-retardant polyolefin resin composition having superior molding processability, a resistance to thermal deformation and suitable stretchability and intensity, which is rich in elastic deformation. The present invention provides a flame-retardant polyolefin resin composition comprising component A (a thermoplastic resin having a carbonyl oxygen atom in the molecular skeleton), component B (a polymer alloy containing an ethylene component and a propylene component), component C: a modified polyolefin polymer containing an acidic functional group and having a weight average molecular weight of 10,000-80,000 and component D (an inorganic metal compound), and substantially free of a halogen atom.