An artificial blood vessel has a trunk portion which forms a part of the blood vessel and also has branch portions which are branched from the trunk portion. The branch portions are provided with access ports into which a needle, for discharging liquid out of a human body or introducing the liquid into the human body, is inserted. Tubular reinforcement members integrated with the blood vessel wall of the trunk portion are disposed at positions of the trunk portion, the positions being those from which the branch portions are branched, and at portions adjacent to the positions of the trunk portion. A lateral force at the time of needle insertion is borne by the reinforcement member, and this prevents the trunk portion from deforming. Thus, the configuration prevents the artificial blood vessel from deforming due to a force applied when a needle for discharging liquid from a human body or introducing the liquid into the human body is inserted into an access port of the artificial blood vessel.
