To provide a power supply device which can properly suppress a rush current at powering-on and heat generation at normal operation without the need for any control, and to provide an air cleaner using the power supply device.

The power supply device comprises a power feeding circuit (AC-DC conversion circuit 301) which feeds drive power to loads (fan motor 101 and DC-AC conversion circuit 302), and a load characteristic thermistor 306 which is arranged on a power feeding line to the loads from the power feeding circuit, and whose resistance value is decreased as a temperature rises.