An impact tool enables a front cover part to be easily attached to and detached from a housing body, with a device having a simplified structure. The front cover part has an annular fastening portion clamped to the outer peripheral surface of a front edge portion of the housing body, a cylindrical portion extending from the front end of the housing to the region of the fastening portion, and a connecting portion connecting together the cylindrical portion and the fastening portion. The fastening portion is split at a circumferential part thereof to form a pair of circumferentially opposing tongue-shaped portions. A clamping device is provided between the tongue-shaped portions, which is movable between a clamping position where it pulls the tongue-shaped portions toward each other and an unclamping position where the tongue-shaped portions are released from being pulled toward each other.