A living body lumen treatment system includes a sheath that internally has a receiving lumen, and a stent that is received in a contracted state by the receiving lumen and that expands by being exposed from the sheath. A first region to which a drug is applied and a second region to which the drug is not applied are set to be located on an outer surface of the stent. The sheath has a protrusion portion protruding beyond an inner wall. In the stent, the second region is brought into contact with and supported by the protrusion portion so as not to bring the first region into contact with the inner wall.
