A mobile lifter including a cylindrical casing supported on a stand, a plurality of inner tubes that slide one inside another and received in the cylindrical casing, a set of pulleys respectively mounted on the inner tubes at different elevations, a winch wound round with a cable, the cable having one end fixed to and wound round the winch and an opposite end inserted in pulleys and then fixed to the bottom end of said fourth inner tube, and a driving mechanism mounted on the cylindrical casing on the outside and controlled to turn the winch, causing it to take up or let off the cable so as to lift or lower the mobile lifter.