To provide an axle housing for reducing manufacturing cost and weight, and a hydroforming method and device.

The axle housing 1 wherein tube material 21 is housed in a die 22, and fluid pressure is applied to the inside of the tube material 21, thereby forming an expanded tube part, is provided with a banjo part 2 composed of a central cylindrical part 5 formed by expanding a tube part in a sectional polygonal shape, and a different diameter tube part 6 formed by connecting both sides of the central cylindrical part 5 and the tube material 4.