Electropolish/grinding means for an inner surface of a long tube

The present invention is an electropolishing/grinding means for an inner surface of a long tube, which comprises at least one long tube, one electrode, at least two partitions, one fixed magnet mechanism, one driving apparatus and an axial driven mechanism; wherein, cooperation of the partitions, the fixed magnet mechanism and the driving apparatus is to form a magnetic levitation effect, which means using magnetic repulsiveness and magnetic attraction to keep away from the partitions and inner surface and avoid the eccentric situation; further, one of the two partitions has plural springs, plural protruding objects and plural abrasives to cooperate each other for firmly the abrasives touching onto the inner surface.