To provide a rush current limiting circuit that enables stable suppression of rush current regardless of environmental conditions, such as ambient temperature, ensures low circuit loss, and can be simply configured.

The rush current limiting circuit has a switch 20 which connects to a path of rush current flowing from the output of a rectification circuit 14 and passes through a smoothing capacitor 16 and whose connection/disconnection is controlled by a switch control signal. A switch control unit 22 that generates switch control signals includes a rectified voltage detection means 26 that detects the rectified voltage of the rectification circuit 14 and a smoothed voltage detection means 28 that detects the smoothed voltage of the smoothing capacitor 16. The switch control unit 22 further includes a switch control signal generating means 30 that receives the results of detection by each detection means and generates a switch control signal. The switch control signal generating means 30 generates a switch control signal for turning on the switch during a period during which the waveform of rectified voltage is of downward pitch, the smoothed voltage is lower than the rectified voltage, and the difference between them is equal to or smaller than a first reference voltage.