To provide a die with which a hollow shaft with a projection is formed at small internal pressure load without generating inside surface flaws and outside fins, and a forming method for the shaft.

Upper and lower dies 2, 3 are respectively provided with at least one or more sets of projection part forming dies 1. The projection part forming die 1 is composed of dies 2c, 2e, 3c, 3e for forming the side wall of the projection part and dies 2d, 3d for forming the upper surface of the projection part. The dies 2c, 2e, 3c, 3e for forming the side wall are bisected in the direction perpendicular to a housed metallic tube stock A. The dies 2d, 3d for forming the upper surface of the projection part are fit into the side wall forming dies 2c, 2e, 3c, 3e so that a caliber of an inside surface shape having the same shape as the contour shape of the projection part is formed together with the side wall forming dies 2c, 2e, 3c, 3e and the each die is made slidable in the axial direction of the housed metallic tube stock A.