PURPOSE: To obtain an electric instrument box for an air-conditioning machine, which is capable of cooling electric parts which generate heat and reducing the temperature of the heat of exhaust gas from the electric instrument box by cold air released from the low-pressure side refrigerant pipeline itself of the air-conditioning machine.

CONSTITUTION: A L-shape notch 14 for passing a refrigerant pipeline is provided at first at the lower side of the rear part of an electric instrument box 13, then, a bottom plate 15, provided with slits so as to improve ventilating property, is provided at the front surface of the notch part 14 whereby a cavity for arranging a refrigerant pipeline is formed at the lower side of the rear part of the electric instrument box 13 to pass a refrigerant pipeline 16 therethrough. Cold air from the refrigerant pipeline 16 can be utilized directly to cool electric parts which generate heat and reduce the temperature of the heat of exhaust gas from the electric instrument box 13 whereby efficient cooling can be effected.