A power cable comprising: a conductor; an inner semiconducting layer covering the conductor; and an insulating layer covering the inner semiconducting layer, wherein the insulating layer comprises, as a base resin, a non-cross-linked thermoplastic resin, which is a blended resin of a polypropylene resin A and a heterophasic resin B in which a propylene copolymer is dispersed in a polypropylene matrix, the content of the polypropylene resin A is 30 to 60 parts by weight and the content of the heterophasic resin B is 40 to 70 parts by weight, based on 100 parts by weight of the base resin, the polypropylene resin A comprises a random propylene-ethylene copolymer containing an ethylene monomer in an amount of 1 to 10% by weight, based on a total weight of monomers, the polypropylene matrix contained in the heterophasic resin B comprises a propylene homopolymer, and the content of the propylene copolymer is 60 to 90 % by weight, based on a total weight of the heterophasic resin B, and a brittleness temperature Tb is in a range of -55 to - 35 °C, the brittleness temperature Tb being defined by the following Equation 1: T b = T h + Δ T S/100 − 1 / 2, wherein T h represents a temperature (°C) at which all five samples are destroyed or cracks observable with a naked eye occur on surfaces of the samples, when, according to ASTM D746, the five samples are left at 23 °C and under relative humidity of 50% for forty hours or more and thereafter are left at each temperature for 2.5 to 3.5 minutes while reducing a temperature by 5 °C and are struck using a striking edge at a speed of 1800 to 2200 mm/s in a direction of an angle of 90 degrees, the samples being manufactured to a thickness of 2 mm by preheating the base resin, for forming an insulating layer, at 180 °C for ten minutes, pressurizing the base resin at 20 MPa for ten minutes, and cooling the base resin, ΔT is 5 °C, and S represents the sum of percentages of samples destroyed at each temperature among all the samples. a conductor; an inner semiconducting layer covering the conductor; and an insulating layer covering the inner semiconducting layer, wherein the insulating layer comprises, as a base resin, a non-cross-linked thermoplastic resin, which is a blended resin of a polypropylene resin A and a heterophasic resin B in which a propylene copolymer is dispersed in a polypropylene matrix, the content of the polypropylene resin A is 30 to 60 parts by weight and the content of the heterophasic resin B is 40 to 70 parts by weight, based on 100 parts by weight of the base resin, the polypropylene resin A comprises a random propylene-ethylene copolymer containing an ethylene monomer in an amount of 1 to 10% by weight, based on a total weight of monomers, the polypropylene matrix contained in the heterophasic resin B comprises a propylene homopolymer, and the content of the propylene copolymer is 60 to 90 % by weight, based on a total weight of the heterophasic resin B, and a brittleness temperature Tb is in a range of -55 to - 35 °C, the brittleness temperature Tb being defined by the following Equation 1: T b = T h + Δ T S/100 − 1 / 2, wherein T h represents a temperature (°C) at which all five samples are destroyed or cracks observable with a naked eye occur on surfaces of the samples, when, according to ASTM D746, the five samples are left at 23 °C and under relative humidity of 50% for forty hours or more and thereafter are left at each temperature for 2.5 to 3.5 minutes while reducing a temperature by 5 °C and are struck using a striking edge at a speed of 1800 to 2200 mm/s in a direction of an angle of 90 degrees, the samples being manufactured to a thickness of 2 mm by preheating the base resin, for forming an insulating layer, at 180 °C for ten minutes, pressurizing the base resin at 20 MPa for ten minutes, and cooling the base resin, ΔT is 5 °C, and S represents the sum of percentages of samples destroyed at each temperature among all the samples.