A hermetically sealed motor compressor for use in a small-size refrigerating machine, refrigerator, freezer and the like has a compressor on which is mounted a silencer comprising in combination a suction muffler of thermal insulating and a discharge muffler made of formed metal plates. The suction muffler has an suction port disposed near the open end of a suction coupling fixed to a sealed casing, and also has an connection pipe connected to a compressor cylinder and having a distal end fitted directly in a hole defined in an head plate which is mounted on the head of the cylinder. A refrigerant gas as it is introduced from the suction coupling into the sealed casing can be drawn into the cylinder through the suction port, the suction muffler and the connection pipe to minimize heat transfer to the suction gas, so that the compressor can increase its volumetric efficiency.