A high-pressure tank which is capable of improving the strength of a connecting part between a cylindrical part and a dome part is provided. A high-pressure tank 10 according to the present invention comprises: a liner 20 having a cylindrically-shaped cylindrical part 20a and hemispherically-shaped dome parts 20b which are continuous with both ends of the cylindrical part 20a; and a reinforcing layer 30 including a fiber bundle which is hoop-wound around the cylindrical part 20a of the liner 20 and a fiber bundle which is helically wound around the dome parts 20b thereof. An outer diameter of the end of the cylindrical part 20a is smaller than an outer diameter of a portion of the cylindrical part 20a which excludes the end.