A hydraulic press such as a press brake is disclosed having a pair of long movable and fixed tools which are always kept in parallel with each other by detecting the obliquities of the movable and fixed tools and controlling the fluid delivery to hydraulic motors which drive the movable tool. Each hydraulic motor is controlled by a valve which is actuated by a rocking cam arrangement. The limit of movement of the movable tool toward the fixed tool also can be easily adjusted by adjusting the rocking cam arrangement.