PURPOSE: To provide a charging device wherein an outer diameter dimension is compacted to be convenient for carrying and using.

CONSTITUTION: In a casing 1, a charging device is composed of a battery pack 6, having a chargeable battery, a charging circuit, an input terminal 4a, an output terminal 4b, and a retractable plug blade 5 and a quick battery charger having a battery pack connection terminal and on which the battery pack 6 is mountable. The charging circuit built in the battery pack 6 and the charging circuit of the quick battery charger are set so as to output different electric power. At the time of normal charge, the plug blade 5 of the battery pack 6 is inserted in a receptacle to perform charging, and at the time of quick charge, the quick battery charger is set to perform quick charge.