The objective of the present invention is to improve the operability of an operation to implant a stent fitted onto a balloon of a catheter into a blood vessel. A stent supply device used to implant a stent (4) fitted onto a balloon (3) into a vessel is provided with a stent holding member (2) which covers and supports the stent fitted onto the balloon from the outer peripheral side thereof. The stent holding member includes: a stent holding body (15) obtained by organizing a filament material (16) into a tubular shape having a length sufficient to cover the entire length of the stent fitted onto the balloon and a withdrawing operation portion (19) which is withdrawn from a proximal end side of the stent holding member and extends along a catheter (1). The tubular shape of the stent holding body is maintained by means of a shape maintaining layer (18) comprising a synthetic resin material attached to the stent holding body to cover the same. The stent holding body is operated to move relative to the catheter by means of the withdrawing operation portion, and is moved from a position covering the balloon and the stent to a position in which the support thereof is released, allowing the stent to be diametrically expanded by the balloon.La présente invention vise à améliorer la facilité de mise en œuvre dune implantation dune endoprothèse emmanchée sur un ballonnet dun cathéter dans un vaisseau sanguin. Un dispositif de mise en place dendoprothèse destiné à implanter une endoprothèse (4) emmanchée sur un ballonnet (3) dans un vaisseau est muni dun élément de retenue dendoprothèse (2) qui recouvre et qui soutient lendoprothèse emmanchée sur le ballonnet depuis le côté périphérique externe de ce dernier. Lélément de retenue dendoprothèse comprend : un corps de retenue dendoprothèse (15) obtenu par organisation dun matériau filamenteux (16) en une forme tubulaire présentant une longueur suffisante pour recouvrir toute la longueur de lendoprothèse emmanchée sur le ballonne
