To avoid increase in the size and cost of a motor and a power supply circuit in a refrigerator or a freezer by preventing increase of a current at the time of starting the operation.

A motor 25 for driving a compressor 21 constituting a refrigeration cycle is speed controlled by an inverter circuit 31. When the inner temperature Tx detected by an inner temperature sensor 35 is not lower than a specified level (e.g. 5°C in case of a refrigerator and -18°C in case of a freezer), a microcomputer 34 retains the rotational speed of the motor 25 at a low level through the inverter circuit 31 thus limiting a current flowing through the motor 25 and a power supply circuit 40. Rotational speed of the motor 25 is controlled to increase as the inner temperature Tx is lowered and cooling rate in the refrigerator or freezer 10 is quickened while suppressing the current flowing through the motor 25.