To prevent even a load not related to the occurrence of an abnormal current from being disabled caused by breaking all the electrical connections with a battery.

In this power connecting device, loads 17A1 to 17Nn on a vehicle are connected to a battery 3 via circuit switch means 23A to 23N, which break the connection of the loads 17A1 to 17Nn to the battery 3 when an abnormal current is detected. The number of circuit switching means 23A to 23N is less than that of the loads 17A1 to 17Nn, but at least two means are provided. The loads 17A1 to 17Nn are classified into the same number of load groups 17A to 17N with that of the circuit switching means 23A to 23N. Then, each of the load groups 17A to 17N is independently connected to the battery 3 via each of the circuit switching means 23A to 23N.