An endoscopic treatment device (10a, 10b) which is configured to be used with an endoscope including an insertion section having a treatment device raiser (66, 68), and a treatment device insertion channel provided along the insertion section, and which is insertable into the insertion channel of the endoscope, the endoscopic treatment device (10a, 10b) comprising: a flexible tube including a distal end portion, a proximal end portion and a lumen connecting the distal end portion and the proximal end portion, and the flexible tube being configured to be inserted into the treatment device insertion channel; a treatment portion configured to project and retract from the distal end portion of the flexible tube, the treatment portion being rotatable about the axial direction of the flexible tube; an operation handle disposed on the proximal end of the flexible tube; and a movable body which includes a distal end connected to the treatment portion, and a proximal end connected to the operation handle wherein the movable body is inserted into the lumen of the flexible tube and is configured to move along the axial direction and to move the treatment portion along the axial direction in accordance with the movement of the operation handle, the movable body comprising an operation wire and a direction control member connected to the distal end of the operation wire, the direction control member configured to be bent in a first direction perpendicular to the axial direction, and in a second direction perpendicular to the first direction and the axial direction, with a force greater than in the first direction being required for bending in the second direction, wherein: when the flexible tube is bent by the treatment device raiser (66, 68), the direction control member is rotationally moved about its longitudinal axis until the first direction of the direction control member coincides with the bending direction of the flexible tube such that the treatment portion is in a predetermined orientation with respect to the insertion section of the endoscope which predetermined orientation is defined by the bending direction of the direction control member and the flexible tube characterised in that the orientation of the direction control member with respect to the axial direction is independent from any rotational position of the flexible tube relative to the insertion section of the endoscope. a flexible tube including a distal end portion, a proximal end portion and a lumen connecting the distal end portion and the proximal end portion, and the flexible tube being configured to be inserted into the treatment device insertion channel; a treatment portion configured to project and retract from the distal end portion of the flexible tube, the treatment portion being rotatable about the axial direction of the flexible tube; an operation handle disposed on the proximal end of the flexible tube; and a movable body which includes a distal end connected to the treatment portion, and a proximal end connected to the operation handle wherein the movable body is inserted into the lumen of the flexible tube and is configured to move along the axial direction and to move the treatment portion along the axial direction in accordance with the movement of the operation handle, the movable body comprising an operation wire and a direction control member connected to the distal end of the operation wire, the direction control member configured to be bent in a first direction perpendicular to the axial direction, and in a second direction perpendicular to the first direction and the axial direction, with a force greater than in the first direction being required for bending in the second direction, when the flexible tube is bent by the treatment device raiser (66, 68), the direction control member is rotationally moved about its longitudinal axis until the first direction of the direction control member coincides with the bending direction of the flexible tube such that the treatment portion is in a predetermined orientation with respect to the insertion section of the endoscope which predetermined orientation is defined by the bending direction of the direction control member and the flexible tube the orientation of the direction control member with respect to the axial direction is independent from any rotational position of the flexible tube relative to the insertion section of the endoscope.