ENDOSCOPIC TREATMENT DEVICE

A clip device includes a clip, including a plurality of arms having sliding grooves; and an intermediate member inserted into the sliding grooves for connecting the plurality of arms; a pressing tube accommodating a proximal end portion of the clip; a connection member connecting with an operation wire at a proximal end side and including an engaging portion engaging with the intermediate member; and a locking mechanism for lock the plurality of arms when the clip is pulled toward the proximal end side by a predetermined distance by the connection member, wherein the clip includes a contact portion formed on a side surface of the arm to be in contact with the engaging portion from a direction orthogonal to an axial direction of the intermediate portion for preventing a deformation of the engaging portion when the intermediate portion slides along the sliding groove before the plurality of arms are locked.