Detection device for a wheel hub assembly provided with a rolling bearing, the detection device having a phonic wheel made of magnetized material and mounted on a rotating ring of the bearing, a shaped support element angularly constrained to the rotating ring of the bearing arranged directly between the phonic wheel and the rotating ring so as to angularly lock together the phonic ring and the rotating ring, and a sensor facing the phonic wheel; a protection device being integral with the rotating ring of the bearing so as to protect simultaneously both the phonic wheel and the sensor from external contaminants.