A sealing device for wheel hubs connected to constant-velocity joints including a first sealing assembly arranged between inner and outer rings of the wheel hub, and a second sealing assembly mounted on the inner ring and straddling the wheel hub and an outer ring of the constant-velocity joint. The first sealing assembly has a signal generating element having an annular insert mounted externally on a shield facing the constant-velocity joint and extending axially projecting above part of an annular step formed, on the same side as the constant-velocity joint, on a radially outer side surface of the inner ring, in a position immediately adjacent to the sleeve portion of the first shield. The second sealing assembly includes a tubular support keyed onto the inner ring by its first end on the outside edge folded in the manner of an L and shaped to engage inside the annular insert.