A power supply controller includes a semiconductor switching element disposed on a current supply line from a power source to a load. The semiconductor switching element is switched between ON and OFF for controlling power supply to the load. A short anomaly of the semiconductor switching element is determined if at least one of an input-to-output voltage of the semiconductor switching element being smaller than a first threshold and the semiconductor switching element being in an ON state is detected, when an OFF signal for instruction to turn OFF the semiconductor switching element is received.