To provide a transient noise reducing circuit for suppressing transient noise generated by fusing of a fuse.

The transient noise reducing circuit is provided with a power source 4, a load device 5 acting by supply of power from the power source 4, a power source switch 2 for switching opening/closing of connection between the power source 4 and the load device 5, the fuse 1 for cutting overcurrent when the circuit is abnormal, a coil 10 imitatively expressing inductance (L) components existing in wiring material, parts of this circuit and the like, and a capacitor (capacitive element) 3 arranged parallel to the fuse 1. By connecting the capacitor (capacitive element, varistor, etc.) 3 parallel to the fuse 1, current change I of formula 2, I=V/R... is lowered by making abnormal current just after fusing of the fuse 1 flow to this capacitor 3.