To provide an in-vivo indwelling stent and an organ dilator, when inserting the stent into a blood vessel, scarcely forming a projection caused by a bend part and prevented from being caught with the blood vessel inner wall.

This stent 1 is formed into an approximately tubular body, has a diameter for being inserted in an organism lumen and, when a radially expanding force is applied thereto from the inside of the tubular body, being dilatable. The stent 1 is disposed with a plurality of annular units 4, each of which is composed of a plurality of annular linear bodies 2 having bend parts in their axially tip sides and rear end sides, and connecting parts 3 connecting the plurality of annular linear bodies 2 into an annular shape, in the direction of the axis of the stent; and is provided with a coupling part 5 coupling the annular units in the axial direction. The annular linear body 2 is so formed that the length from the connecting part 3 to the vertex of the tip side bend part 21 is shorter than the length from the connecting part 3 to the vertex of the rear end side bend part 22.