A sealing device for a wheel hub unit configured to form a static seal to protect the wheel hub unit from environmental contaminants. The sealing device including a metal shield that is coupled to a collar of the wheel hub unit, and has an end wall, a cylindrical lateral wall integral with, and orthogonal to, the end wall. The lateral wall has twice the thickness of the end wall in order to impart stiffness to the metal shield, and a stop edge integral with the cylindrical lateral wall on the opposite side to the end wall, for bearing axially against the collar; a sealing gasket formed by a silicone-based sealing compound being provided to allow the formation of a bead against a cylindrical lateral wall in an assembly configuration of the sealing device.