A treatment tool comprising: a long shaft member having a distal end portion and a proximal end portion, and a longitudinal axis extending from the distal end portion to the proximal end portion; a pair of grasping members installed at the distal end portion of the long shaft member so as to be freely opened and closed with each other to grasp a target area; a driving force transmission member connected to the pair of grasping members and extending along the longitudinal axis so as to be freely moved along the longitudinal axis with respect to the long shaft member; a driving manipulation member connected to a proximal end portion of the driving force transmission member and configured to be capable of being manipulated so that the driving force transmission member moves with respect to the long shaft member; and a manipulation unit main body installed at the proximal end portion of the long shaft member, wherein the driving manipulation member is movable with respect to the manipulation unit main body, characterized by a switch unit configured to switch a moving state of the driving manipulation member with respect to the manipulation unit main body into a moving state of one of a first state in which the driving manipulation member is rotated about a first rotational center with respect to the manipulation unit main body by a first sliding section (25; 25A) supporting the driving manipulation member and a second state in which the driving manipulation member is rotated about a second rotational center different from the first rotational center with respect to the manipulation unit main body by a second sliding section (26; 26A) formed continuously to the first sliding section (25; 25A) supporting the driving manipulation member. a long shaft member having a distal end portion and a proximal end portion, and a longitudinal axis extending from the distal end portion to the proximal end portion; a pair of grasping members installed at the distal end portion of the long shaft member so as to be freely opened and closed with each other to grasp a target area; a driving force transmission member connected to the pair of grasping members and extending along the longitudinal axis so as to be freely moved along the longitudinal axis with respect to the long shaft member; a driving manipulation member connected to a proximal end portion of the driving force transmission member and configured to be capable of being manipulated so that the driving force transmission member moves with respect to the long shaft member; and a manipulation unit main body installed at the proximal end portion of the long shaft member, wherein the driving manipulation member is movable with respect to the manipulation unit main body, characterized by a switch unit configured to switch a moving state of the driving manipulation member with respect to the manipulation unit main body into a moving state of one of a first state in which the driving manipulation member is rotated about a first rotational center with respect to the manipulation unit main body by a first sliding section (25; 25A) supporting the driving manipulation member and a second state in which the driving manipulation member is rotated about a second rotational center different from the first rotational center with respect to the manipulation unit main body by a second sliding section (26; 26A) formed continuously to the first sliding section (25; 25A) supporting the driving manipulation member.