A treatment tool for an endoscope of the present invention includes a sheath, a balloon provided at a distal end of the sheath and configured to be expandable to an inflated state from a reduced diameter state by injecting a fluid, and an adhering portion provided on a side of an inner surface of a central portion of the balloon in a direction of a longitudinal axis of the sheath and configured to hold the central portion in a reduced diameter state, wherein the balloon is configured so that, when the fluid is injected and an internal pressure of the balloon is equal to or lower than a first internal pressure, sticking of the central portion and the adhering portion is held, and only a distal end portion located on a distal end side from the central portion, and a proximal end portion located on a proximal end side from the central portion inflate, and when the internal pressure of the balloon is higher than the first internal pressure, the adhering portion is peeled off and the central portion inflates.
