Abstract: Acoordination factor for the sequence of plans was proposed aimed to coordinating the casting production plan with the hot rolling production plan in an integrated production process.An optimization model of the hot-rolling batch plan available to improve the direct hot charging rolling(DHCR) proportion was established.On the basis of meeting the requirements of the hot rolling process,the model considers well the coordination of the casting production plan and the hot rolling production plan.A modified genetic algorithm,the two-exchange crossover heuristic algorithm,was used to solve the model.Finally,two slab groups which are large batch quantity with seldom types and small batch quantity with multiple types were simulated in the 2 250 mm hot rolling line and the 1 580 mm hot rolling line in a steel plant.The results show that the model could greatly reduce the waiting time of slabs caused by the casting slab sequence conflicts before entering the reheating furnace,and the DHCR proportion is increased correspondingly.