An apparatus for covering a plurality of permanent magnets on a rotor with a cylindrical sleeve has a movable jig, a holder jig having a plurality of insertion grooves for inserting therein the permanent magnets disposed in grooves of the rotor, the holder jig and the movable jig being pressable partly into an insertion end of the cylindrical sleeve, a plurality of resilient members disposed in the insertion grooves for pressing the permanent magnets against the outer circumferential surface of the rotor, and a presser device for inserting the movable jig, together with the rotor and the permanent magnets into the cylindrical sleeve under the guidance of the holder jig. The permanent magnets on the rotor are reliably and efficiently covered with the cylindrical sleeve without the need for an adhesive to secure the permanent magnets to the rotor.