An endoscope treatment tool (1, 51, 81) comprising: a pair of clamp members (11, 12, 61, 62, 91) that is supported by a clamp rotary shaft (13, 65, 94) to be relatively rotatable; an operation section that is used to open and close the pair of clamp members (11, 12, 61, 62, 91); an operation wire that connects the pair of clamp members (11, 12, 61, 62, 91) to the operation section; a connection member that is provided at the front end of the operation wire and includes two link rotary shafts (34A, 34B); a pair of link members (35, 36) of which a first end is rotatably connected to each end of the pair of clamp members (11, 12, 61, 62, 91) and a second end is rotatably connected to the link rotary shafts (34A, 34B); and a regulation portion (33, 71, 71A, 71B), wherein the pair of link members (35, 36) are set to be parallel to each other in the state where the pair of clamp members (11, 12, 61, 62, 91) are closed, wherein the connection member includes a groove formed to be parallel to the axis of the operation wire, characterised in that the regulation portion (33, 71, 71A, 71B) is disposed to be parallel to an axis of the operation wire, passing through the inside of the groove of the connection member to regulate the relative movement direction of the operation wire and the connection member with respect to the clamp rotary shaft (13, 65, 94), wherein, in the regulation portion (33, 71, 71A, 71B), a first end is connected to the clamp rotary shaft (13, 65, 94), and a second end is connected to the body of the operation section through an insertion portion, and wherein the regulation portion (33, 71, 71A, 71B) is configured to regulate rotations of the pair of link members (35, 36) being over a position in which the pair of link members (35, 36) come into contact with the regulation portion (33, 71, 71A, 71B) in a direction in which the pair of link members (35, 36) comes close to the regulation portion (33, 71, 71A, 71B). a pair of clamp members (11, 12, 61, 62, 91) that is supported by a clamp rotary shaft (13, 65, 94) to be relatively rotatable; an operation section that is used to open and close the pair of clamp members (11, 12, 61, 62, 91); an operation wire that connects the pair of clamp members (11, 12, 61, 62, 91) to the operation section; a connection member that is provided at the front end of the operation wire and includes two link rotary shafts (34A, 34B); a pair of link members (35, 36) of which a first end is rotatably connected to each end of the pair of clamp members (11, 12, 61, 62, 91) and a second end is rotatably connected to the link rotary shafts (34A, 34B); and a regulation portion (33, 71, 71A, 71B), wherein the pair of link members (35, 36) are set to be parallel to each other in the state where the pair of clamp members (11, 12, 61, 62, 91) are closed, wherein the connection member includes a groove formed to be parallel to the axis of the operation wire, characterised in that the regulation portion (33, 71, 71A, 71B) is disposed to be parallel to an axis of the operation wire, passing through the inside of the groove of the connection member to regulate the relative movement direction of the operation wire and the connection member with respect to the clamp rotary shaft (13, 65, 94), wherein, in the regulation portion (33, 71, 71A, 71B), a first end is connected to the clamp rotary shaft (13, 65, 94), and a second end is connected to the body of the operation section through an insertion portion, and wherein the regulation portion (33, 71, 71A, 71B) is configured to regulate rotations of the pair of link members (35, 36) being over a position in which the pair of link members (35, 36) come into contact with the regulation portion (33, 71, 71A, 71B) in a direction in which the pair of link members (35, 36) comes close to the regulation portion (33, 71, 71A, 71B).