An endoscopic treatment tool includes a sheath; a treatment portion; and a manipulation main body which includes a distal end-fixing portion capable of being fixed to a proximal end side-opening portion, an intermediate portion connected to a proximal end of the sheath and advances and retracts in a longitudinal axis direction of the sheath, a proximal end-manipulating unit which slides with respect to the intermediate portion, a fixing member, and a support member. One of the distal end-fixing portion and the intermediate portion is inserted and connected to the other thereof to partially overlap each other in the longitudinal axis direction, the support member is rotatably engaged with a member disposed on an outer side among the distal end-fixing portion and the intermediate portion, and the support member is configured to be able to fix the fixing member at an arbitrary-position of the manipulation main body in the circumferential direction.