An internal combustion engine comprising: a combustion chamber surrounded by at least an inner wall of a cylinder bore, a cylinder head, a valve and a piston, and a coating layer arranged on at least part of the inner wall of the combustion chamber, wherein the thermal conductivity of the coating layer is, at room temperature, lower than the thermal conductivities of the cylinder block, the cylinder head, the valve and the piston, the thermal conductivity of the coating layer is reversibly increased along with a rise in the temperature of the coating layer, and wherein the heat capacity per unit area of the coating layer is more than 0 kJ/(m2·K) and 4.2 kJ/(m2·K) or less.