To provide the same effect as in a simulation rapidly and rely without increasing a system load.

A method is formed so that a process is classified into large categories in the flow direction and coded in the unit of process included in each of the large categories as to in what order articles are made to flow specifically in the large categories, a production process is determined by its enumeration, and a process series thus obtained is controlled by a several digits of code summarized regularly according to process equipment. When an operating error occurs, a process code for changing operation according to an error code is retrieved from a table to which the process code is registered beforehand, and a process on the downstream side is changed from a standard process to a process for changing operation. Thus the control of physical distribution and the charge of process planning can be changed rapidly and effectively.