The invention discloses a floating block of a hub shaping die. The floating block comprises point-shaped internal bracing sheets and toothed external pressing sheets; a convex cambered surface is arranged on one side of each point-shaped internal bracing sheet; a plurality of convex bracing points are formed on each convex cambered surface; each toothed external pressing sheet is in a semicircular structure; concave cambered surfaces are arranged on the inner side surfaces of the semicircular structures, and are matched with the convex cambered surfaces; a plurality of pressing teeth are formed on each concave cambered surface, and are formed in the thickness direction of the corresponding semicircular structure; the convex bracing points and the pressing teeth are arrayed in a staggered manner. The floating block further comprises an internal driving mechanism and an external driving mechanism; the internal driving mechanism drives the point-shaped internal bracing sheets; the external driving mechanism drives the toothed external pressing sheets; and the point-shaped internal bracing sheets are fitted with or separated from the toothed external pressing sheets through the internal driving mechanism and the external driving mechanism. A hub is clamped through the point-shaped internal bracing sheets and the toothed external pressing sheets, and is stressed by the point-shaped internal bracing sheets and the toothed external pressing sheets at a deformation part, thereby achieving the shaping effect.