An embodiment may inhibit, in a simpler manner, the theft of a battery pack capable of being attached to and detached from a portable electric work machine. An electric brush cutter is provided with: a battery pack capable of assuming either a sleep state or an active state; and a work-machine main body. The battery pack is provided with a memory having, stored therein, information indicating the state of a battery. The brush cutting work-machine main body is provided with: a work unit and a work-machine controller for controlling the work unit. The work-machine controller prohibits operation of the work unit when the information stored in the memory of the battery pack indicates the sleep state, and enables operation of the work unit when the information stored in the memory of the battery pack indicates the active state.