A driving apparatus of a motor capable of operating a motor of a reciprocating compressor stably by using a simple power voltage control unit. The apparatus includes a power voltage control unit for maintaining a power voltage supplied from a power supply unit as a certain value when a motor is operated, outputting the certain power voltage or cutting off the power voltage after a certain time has passed; and a capacitor for applying the power voltage supplied from the power supply unit to the motor when the power voltage control unit cuts off the power voltage.