To provide a suture instrument for an endoscope which can lift a diseased tissue in a wide range for performing en bloc resection of the diseased tissue in full thickness. A suture instrument for an endoscope which is attachable to an endoscope that is able to be inserted into a body cavity from a distal side, includes: a device including a lift instrument that grasps a living tissue located at a predetermined grasping position to lift the living tissue in a thickness direction of the living tissue, and a forward expansion section that pinches the living tissue lifted by the lift instrument and a suture device that sutures the living tissue pinched in the device, wherein the forward expansion section includes a living-tissue-introducing section that extends and retracts in a direction intersecting the living tissue lifted by the lift instrument to be contacted with the living tissue.
