With the principle of elastic-plastic theory applied, it uses pressure head to straighten and shape the curved or irregular section profiles or sheets. It is widely used in mechanical industry and metallurgical industry. It uses hydraulic pressure to drive the head, with features of a large and stepless leveling force adjustable, head moving transverse, large operation table, a variety of layout, easy operation and maintenance and so on. It is applied in the heavy plate workshop of steel mill, and it meets the need for leveling of medium and heavy plates, especially suitable for work situation that general leveling machine can not handle with. It can flatten the cold steel plate directly, and it also meets other straightening requirements.