An endoscopic treatment tool comprising: a sheath in which a lumen extending from a distal end to a proximal end of the sheath is formed; an elongated shaft which is inserted into the lumen, is capable of protruding and retracting from the distal end of the sheath, and has an insertion passage in the elongated shaft; a stylet disposed in the insertion passage to be movable relative to the elongated shaft; an implant which is connected to a distal end of the stylet inside the insertion passage and is capable of protruding and retracting from a distal end of the elongated shaft; a manipulation part main body which is provided on a proximal end side of the sheath and is configured to be mounted on an endoscope; a slider which is provided to be advanceable and retractable in an axial direction with respect to the manipulation part main body and is fixed in the axial direction to a proximal end portion of the elongated shaft; and a cam tube which is configured to retract while rotating in accordance with manipulation of the slider, supports a proximal end portion of the stylet, and has a guide passage formed spirally around a central axis of the manipulation part main body, wherein the proximal end portion of the stylet has a projection which is engaged with the guide passage such that a force retracting the stylet is applied to the stylet by the cam tube when the cam tube retracts while rotating, wherein the projection is configured to be slidable within the guide passage, and wherein a lead angle of the guide passage is set such that the stylet is advanceable relative to the elongated shaft against the force retracting the stylet. a sheath in which a lumen extending from a distal end to a proximal end of the sheath is formed; an elongated shaft which is inserted into the lumen, is capable of protruding and retracting from the distal end of the sheath, and has an insertion passage in the elongated shaft; a stylet disposed in the insertion passage to be movable relative to the elongated shaft; an implant which is connected to a distal end of the stylet inside the insertion passage and is capable of protruding and retracting from a distal end of the elongated shaft; a manipulation part main body which is provided on a proximal end side of the sheath and is configured to be mounted on an endoscope; a slider which is provided to be advanceable and retractable in an axial direction with respect to the manipulation part main body and is fixed in the axial direction to a proximal end portion of the elongated shaft; and a cam tube which is configured to retract while rotating in accordance with manipulation of the slider, supports a proximal end portion of the stylet, and has a guide passage formed spirally around a central axis of the manipulation part main body, wherein the proximal end portion of the stylet has a projection which is engaged with the guide passage such that a force retracting the stylet is applied to the stylet by the cam tube when the cam tube retracts while rotating, wherein the projection is configured to be slidable within the guide passage, and wherein a lead angle of the guide passage is set such that the stylet is advanceable relative to the elongated shaft against the force retracting the stylet.