Iron ore sintering having two-layers, with normal coke rate in the top layer and lower coke rate in the bottom layer can significantly reduce the overall coke rate and improve the sinter quality by producing optimum thermal profile and melting fraction throughout the bed height. For optimum design of the two-layer sintering process we have to evaluate the coke rate and thickness of the two layers. The two main objectives of the sintering process are sinter quality and reduction of coke rate, which is investigated here by multiobjective optimization to evaluate the Pareto optimum points, which gives the competitive optimum points with respect to the two conflicting objectives. The total height of the sinter bed can vary significantly in industrial practice, and thermal efficiency or coke rate improves with higher bed height, which however requires higher suction pressure. This study gives a good insight into the effect of sinter bed height on quality and coke rate. Copyright © 2005 IFAC.