To provide an apparatus which treats the morbidity of a bifurcation zone by supporting a vessel wall and making it comparatively easy to arrange.

In a system for carrying an apparatus in which a body vessel is separated into secondary vessels and a main vessel treats a bifurcation zone in which a section increases up to the bufurcation zone, a first stent body, which is extensible so as to be engaged with a primary vessel in the junction zone, is radially self-expansible, has a first end, which has substantially conic shape in a predetermined fully self-expanded condition and a larger diameter than a second end, and is formed so as to be in agreement with the section of the main vessel which increases in the direction of at least one secondary vessel in the expansion succession zone of a bifurcation spot which separates the main vessel from the secondary vessel; the first stent body is cut from a single pipe, and the first end spreads in the direction of the secondary vessel during expansion, and becomes independent of other stent bodies when the first stent body is in a self-expanded condition, and has no means for connecting with the other stent bodies.