In steel works, required amount of ores are transferred from ore yard to down stream plants such as blast furnaces, coke oven furnaces and sintering furnaces. It is necessary to maintain ore stock at a certain levels of all plants to attain stable operations in steel works. However, it is difficult to avoid sudden change in production environment such as shortage of ore supply or demand change in down stream processing. In this paper, regulation of productions in plural blast furnaces for ore supply changes. The problem to be solved is the optimization of production amounts for plural blast furnaces in case of ore stock level changes induce by defects in ore transfer routes. In disasters such as an earthquake, it may occur the destruction of some transfer conveyers between ore yard and blast furnace supplied by the destructed transfer route. At the same time, production plans of other furnaces must be modified to cover the affected furnace. Transfer route schedule of conveyers from ore yard to furnaces are also to be reconstructed. In this paper, agent based regulation of productions for plural furnaces are treated in case of ore supply change accompanied with numerical results.