A basket type treatment tool includes a sheath, a distal end cover attached to a distal end of the sheath and having grooves including first and second grooves, basket wires, and an operating wire, the first groove has first surface in which at least part of bottom surface of the first groove is inclined in a direction along the basket wires that are in a state in which the basket protrudes from the distal end cover, the second groove has second surface in which at least part of bottom surface of the second groove is inclined in a direction along the basket wires, and when the operating wire is pulled through a different one of the plurality of groove sections and abuts one of the first surface and one of the second surface.
