The invention discloses the technology of a steel seamless cylinder outer surface polisher. A machine body is fixed with a motor, a shaft is fixed by a bearing, and a tensioner, a cross seat, a longitudinal seat, a D cylinder, an E cylinder, a material overturning device, an A cylinder, a guide sleeve and a bearing are all fixed; the motor is fixed with a chain wheel, the shaft is fixed with a driven chain wheel, the shaft is fixed with a roller, the bearing is fixed with a swing shaft fixed with a swing arm and a support, a connecting plate is fixed with a screw rod, the E cylinder is fixed with the material overturning device, the cross seat is fixed with a C cylinder and a guide track, a cross motor seat is fixed with a cross motor and a sand wheel shaft seat, a sand wheel shaft is fixed with a cross sand wheel, a longitudinal motor seat is fixed with a longitudinal motor and a longitudinal sand wheel shaft seat, a longitudinal sand wheel shaft is fixed with a longitudinal sand wheel, and the longitudinal seat is fixed with a B cylinder and a track; the chain wheel and the driven chain wheel are movably connected by a chain, the tensioner is movably connected with the chain, the support is movably connected with a driven roller, the swing arm is movably connected with the connecting plate, the guide track is movably connected with the cross motor seat, the cross motor is movably connected with the sand wheel shaft by a belt, the C cylinder is movably connected with the cross motor seat, the track is movably connected with the longitudinal motor seat, the longitudinal motor is movably connected with the longitudinal sand wheel shaft by a plate belt, a B cylinder is movably connected with the longitudinal motor seat, the A cylinder is movably connected with a push rod movably connected with the guide sleeve, and the D cylinder is movably connected with a hook member; the screw rod penetrates through the machine body to be in threaded connection with a nut. The steel seamless cylinder outer surface polisher is used for polishing a cylinder and has good effect.