To simplify structure of a device for clamping a jigsaw blade.

The device for clamping a jigsaw blade is provided with a sleeve (12) attached to a lower end of a plunger (10) of a jigsaw via a torsion spring (13), an end plate (19) positioned at the lower end of the sleeve and having an insertion hole (20) of a blade (11) and a tilting cam surface (21) formed on an upper side of the insertion hole (20) for guiding a projecting piece (11a) on a side edge of the blade, an engaging member (14) having an engaging means (23) which holds the upper end of the blade before twisting the sleeve so that the projecting piece of the blade stays in the insertion hole and allows the projecting piece to pass through the insertion hole when the blade is twisted by a predetermined angle together the sleeve against the energizing force of the torsion spring and allows that the sleeve (12) returns to the original position lifting the projecting piece passed through the insertion hole by the tilting cam surface, and a compression spring (15) enclosed in the plunger for energizing the engaging member toward the end plate.