An electric handheld working machine includes: a housing including: a motor as a drive source of a working unit; an operating handle; and attaching members provided on an outer surface of the housing and configured to attach a battery to supply electric power to the motor. The attaching members includes: a connecting terminal connected to the battery; a step provided above the connecting terminal and configured to function as a drainage path to drain drops of water to sides; and openings formed in the sides of the attaching members to communicate with the drainage path. The openings communicate with a cooling air flow path configured to allow cooing air to flow through a gap between a back surface of the battery attached to the attaching members and the outer surface between the attaching member.