A power supply control device which is capable of allowing a circuit protection function to work effectively while a backup function is provided. The power supply control device (15) is provided with a control part (25) which controls a semiconductor switch (45) to execute on operation when it is judged that no abnormality occurs but to keep an off state when it is judged that abnormality occurs,a monitor part (27) which monitors whether the control part (25) is in a normal or abnormal condition, and switch parts (41, 43) which allow the on/off operation of the semiconductor switch (45) to be controlled by the control part (25) when the result of monitoring by the monitoring part (27) is a normal condition, but allow the on/off operation of the semiconductor switch (45) based on an on/off command signal (S1) provided from outside when the monitoring result is an abnormal condition. The device can be used for a lighting control circuit of a head lamp for a vehicle.