To coordinate an arrangement request for parts required for product production and a product production plan with each other.

Depending on the production standard information, stock information and production plan that storage parts 31, 32 and 33 store respectively, a required-quantity calculation part 21 calculates a prepared quantity of parts arranged for product production. The arranged quantity is stored in an arrangement request storage part 34, and also stored in a production plan-to- arrangement request relevant information storage part 35 with relevancy to the production plan. When a retrieval part 22 for production plans required to be altered retrieves any production plan required to be altered out from the production plan-to-arrangement request relevant information storage part 35, the operator operates an input device 1 to alter the part arranged quantity and the production plan with the help of the functions of an arrangement request alteration part 23 and production plan alteration part 24. Repeating this routine coordinates the part arrangement request and the production plan with each other.