Abstract: An algorithm for solving zone temperature set points optimization of reheating furnace by using heuristic search technique is presented in this paper, based on the discrete state space reheating furnace model developed by the authors. According to the proposed algorithm a hierchical computer control system for slab reheating furnace is designed and implemented. Through over one year's online running, it shows that the proposed system is" both reliable and accurate enough for reheating furnace control. Furthermore, a considerable energy saving (9%) and significant product quality improving have been achieved, thus producing an economic benefit of over 1 million Yan/year.