A wedge setup/control method for plate material rolling ensures that the work side and drive side are equal in the rolled plate thickness. The wedge setup/control method, which is used in reversible rolling of a plate material with a rough mill for hot rolling, includes preparing a wedge meter on the outlet side of the rough mill to measure the plate thickness in the direction of the plate width; performing calculations on a wedge measured by the wedge meter, using the influence coefficient of the wedge for roll gap leveling of the rough mill; determining amount of roll gap leveling control; and exercising feedback control to apply the amount of roll gap leveling control to the roll gap leveling of the rough mill.