The present invention aims to provide an artificial blood vessel which promotes intimal formation after indwelling, and is capable of maintaining antithrombogenicity during the intimal formation, and of maintaining its patency for a long time. The present invention provides an artificial blood vessel which is a tubular fabric comprising, a fiber layer containing an ultrafine fiber(s) and an ultrafine fiber layer in the inside of the fiber layer, the ultrafine fiber layer being composed of an ultrafine fiber(s) having a fiber diameter(s) of 10 nm to 3 µm, wherein an antithrombin agent having a polymer chain other than heparin is covalently bound to the ultrafine fiber via the polymer chain, and the thrombin activity inhibition rate on the fiber surface at 37°C is not less than 60%.
