A treatment tool includes a long shaft member, a pair of grasping members installed at a distal end portion of the long shaft member, a driving force transmission member connected to the pair of grasping member, a driving manipulation member, and a switch unit having a first sliding section and a second sliding section, and configured to switch a ratio of a magnitude of a force for moving the driving force transmission member with respect to a magnitude of a force for moving the driving manipulation member when the driving manipulation member is manipulated to be moved by switching a position at which the driving manipulation member is slid between the first sliding section and the second sliding section.