According to the invention, the system (1) comprises: -a stent (50) having a proximal end -a support (2) comprising the stent (50) engaged thereon, having a longitudinal axis and being equipped with a stop (4) against which the proximal end of the stent (50) is applied -a sheath (5) having a distal end (5a), which can be slid relative to said support (2) and said stop (4), between a distal overlap position of the stent (50) and a proximal release position for the deployment of the stent (50), and -a first inflatable balloon(3) situated between said support (2) and the stent (50), comprising a distal portion (3b) that protrudes past the distal end of the sheath, on the distal side thereofwhen the latter is in said distal position, and having, in the inflated state, over all or part of the length thereof, on the distal side, a transverse section larger than or equal to that of the sheath (5), the distal end (5a) of the sheath (5) being, in said distal overlap position of the stent (50), situated back from said distal end (3b), along said longitudinal axis of the support (2), in the proximal direction, and being situated opposite said distal portion (3a), such that said distal portion protrudes partially past said distal end (5a) of the sheath (5), on the distal side of said end.SYSTÈME DIMPLANTATION DENDOPROTHESE Selon linvention, le système (1) comprend : -une endoprothèse(50) ayant une extrémité proximale -un support (2) comprenant lendoprothèse (50) en prise sur celui-ci, ayant un axe longitudinal équipé dun arrêt (4)contre lequel lextrémité proximale de lendoprothèse (50) sapplique -une gaine (5) ayant une extrémité distale (5a), qui peut glisser par rapport auxdits support (2) et arrêt (4), entre une position de chevauchement distale de lendoprothèse (50) et une position de libération proximale pour le déploiement de lendoprothèse (50), et -un premier ballonnet gonflable (3) situé entre ledit support (2) et lendoprothèse (50), comprenant une partie distale (3b) q