The present invention is a retractor for displacing an organ within the body cavity or the inner wall of a hollow organ, the retractor being provided with: a housing tube an expansion body which can be housed into and extend from the housing tube and a grip connected to the proximal ends of the housing tube and the expansion body. The expansion body is provided with: a displacing part configured from a movable wire and multiple fixed wires disposed in the periphery of the moveable wire and an introduction tube which is disposed along the displacing part and through which the movable wire penetrates. Moreover, when the expansion body is expanded, the displacement part is designed so that, from among the expansion angles formed by two adjacent fixed wires, one expansion angle (θ2) becomes larger than the other expansion angle (θ1).