The utility model relates to a recoverable composite insulator is with preventing unfirmly closing safety cover, this safety cover of its characterized in that includes protective housing, bullet division device, adsorption equipment and controlling means, the device is opened to the bullet and adsorption equipment all installs in the protective housing, through controlling means control bullet division device and adsorption equipment's switch -on and disconnection, the protective housing comprises the identical casing that is semi -cylindrical form of two shapes, and two semi -cylindrical form casings are locks each other, and the insulator is wrapped up in to the lucky energe storage pack of inner space of two semi -cylindrical form casings, all is equipped with the square hole about the radial central plane of protective housing symmetry on the terminal surface at the both ends of every semi -cylindrical form casing, is equipped with two round holes and two branches on the terminal surface of semi -cylindrical form casing one end, the symmetry is provided with two bosss on the medial surface of semi -cylindrical form casing, is provided with the guide arm on every boss, the bullet is opened the device and is included coil, armature and pressure spring, and the dress is joined in marriage on the protective housing through the round hole to the coil, and armature is hook -likely, and armature is articulated with branch.