Abstract: A nonlinear discrete-time state space model describing the temperature distribution of the slabs in awalking beam reheating furnace is advanced based on unsteady state heat conduction equation and relevant boundary conditions through the discretization technique.Also,an integrated optimization technique utilizing nonlincar programming strategy is developed and applied to design a hicrarchical computer control system for the furnace.All these are succssfully implemented on line.The results have shownthat the system is reliable,flexible for control.Better control performance and significant economic benefit are achieved since the system was put into use.