A device for placing a vascular implant including a device for dilating a vessel, has an outer envelope and a tapered end piece for introduction into a vessel. The end piece includes a nose formed at the distal extremity of the outer envelope. The dilation device includes elements for opening the nose having at least two longitudinal slots which divide the nose into several segments which can be opened out in order to open the nose; and an implant which is placed in the outer envelope. The implant includes an expandable element which can be placed in the outer envelope. The implant includes an expandable element which can be placed on the internal wall of the outer envelope and is provided with elements for the translation of the implant in relation to the outer envelope such that the expandable element can press against the internal wall of the nose in order to open out the segments. A device for placing vascular implants fitted with the device is also disclosed.