To decide the optimum pass schedule by which conditions that are not over the limit value is made to stands which are over the limit value while strictly satisfying the mass flow constant regulation at each stand and load distribution ratio of a basic pass schedule is conserved as to the other stand.

By defining a numerical value in which a rolling load ratio to which the correction Δγi of load ratio which is necessary to making the rolling conditions not higher than each limit value is added to a rolling load ratio γi in the basic pass schedule as a corrected target rolling load ration γi* at each standand simultaneously determing the corrected outlet-side thickness hi* at each stand and corrected speed Vi* at each stand so that the corrected target rolling load ratio γi* is satisfied at all stands taking the outlet- side thickness hi at each stand speed Vi at each stand as variables, the optimum pass schedule is decided.