A lens driving device according to the present invention is a lens driving device that includes an auto-focus coil and an auto-focus magnet and that moves a movable auto-focus unit including the auto-focus coil in the direction of an optical axis relative to a fixed auto-focus unit including the auto-focus magnet by using a driving force of a voice coil motor constituted of the auto-focus coil and the auto-focus magnet. The fixed auto-focus unit includes a case formed of a non-magnetic material and having a rectangular shape in plan view and a base on which the case is fixed. The auto-focus magnet has the shape of a flat plate disposed on a side face of the case, and at least one of the four side faces of the case is a non-magnet-disposed face, on which the auto-focus magnet is not disposed.