Abstract: Investigates a method for increasing the positioning accuracy of electric APC (auto position control) system for plate mill while assuring its positioning speed. With a time optimal idea a predetermined screw down path curve was adopted following the electric APC control requirement and the actual conditions of equipment. Intelligent control then enabled the actual screw down path to follow up the predetermined screw down path, in order to guarantee the accurate positioning of electric APC control. This control algorithm has been applied in actual production with a positioning accuracy of up to 0 05 mm, under a substantial system inertia and uncertain friction force in down screws. The whole positioning process remained rapid and without overshoot.