Abstract: A switchable permanent magnetic chuck of the type capable of detachably hold a magnetic work piece. The chuck comprises a frame structure with its top and bottom being open, a work supporting faceplate and a bottom plate to cover the top and bottom openings, respectively, of the frame structure, a plurality of stationary permanent magnets supported on the frame structure and a plurality of movable permanent magnets supported on a shiftable plate which is movably accomodated in the frame structure, and adapted to be operable in association with the stationary permanent magnets to bring the work supporting faceplate into a magnetized or demagnetized condition. In order to reduce the height of the chuck without reducing the magnetic power, permanent magnets having a high coercive force are used as the above-mentioned stationary and movable permanent magnets.