Provided is an end seal structure of a fuel rail for a gasoline direct injection engine, the fuel rail being constructed and arranged such that an end or both ends of a rail body composed of a tubular body such as a pipe is/are closed by an end cap or end caps, the end seal structure having a simple structure, making it possible for the end cap portion to meet higher pressure requirements. The end seal structure, in which an end or both ends of a rail body composed of a pipe is/are closed by a thread fastening type of an end cap or end caps having a cap-nut shape, is characterized in that a metallic gasket is provided between an inner wall surface of the end cap having the cap-nut shape and an end section of the rail body, the end cap having the cap-nut shape is screwed and fixed to the rail body, and the gasket is tightened by an axial force created by tightening of the end cap having the cap-nut shape so that the end of the rail body is sealed.
