A lens driving apparatus includes a holder, a cover, a carrier, a first magnet, a coil, a spring, two second magnets and a hall sensor. The holder includes an opening hole. The cover is made of metal material and coupled to the holder. The carrier is movably disposed in the cover, and for coupling to a lens. The first magnet is connected to an inner side of the cover. The coil is wound around an outer side of the carrier, and adjacent to the first magnet. The spring is coupled to the carrier. The second magnets are disposed on one end of the carrier which is toward the holder. The hall sensor is for detecting a magnetic field of any one of the second magnets, wherein the magnetic field is varied according to a relative displacement between the hall sensor and the second magnet which is detected.