An electric vacuum cleaner according to the present invention boosts a voltage supplied to a motor-driven blower through the use of a boost converter circuit with a DC power supply as a drive source to thereby increase the output of the motor-driven blower so as to enhance dust suction power. The present invention provides, as operation modes of such an electric vacuum cleaner, an operation mode for boosting power inputted to the motor-driven blower with the boost converter circuit to thereby increase dust suction power, and an operation mode for deactivating the boost converter circuit. Consequently, the boost converter circuit is used to enable the boosting of the power inputted to the motor-driven blower only when really required, and a loss in power produced due to the mounting of the boost converter circuit can be reduced. Thus, the service hour per charge for a battery can be set to a level equivalent to an electric vacuum cleaner equipped with no boost converter circuit.