The purpose of the present invention is to provide a sheet derived from a biological tissue, which can be used for the production of a tubular structure that can be used in an artificial blood vessel and has excellent pressure resistance and handling properties. For the purpose of achieving the purpose, the present invention provides: a sheet of a biological tissue, in which the edge part of at least one side has a tapered shape that becomes thin in the thickness direction toward the end of the edge part； a tubular structure produced from the sheet； and an artificial blood vessel comprising the tubular structure.
