The flame-retardant thermoplastic resin, composition comprised of the following Components (C), (D) and (E) with the thermoplastic resin composition having a thermoplastic polyurethane elastomer of the Component (A) and an ethylene polymer and/or an ethylene copolymer of the Component (B) as the main components;Component (C): a (poly) phosphate compound represented by the following general formula (1). n in the formula (1) represents a number of 1-100; X1 is an ammonia; or a triazine derivative, represented by the following general formula (2); p is a number satisfying a relation of 0