PURPOSE: To execute delivery order in such a manner as giving priority to old inventory among all the products stored in each address and keeping high efficiency of delivery work according to delivery instruction, in a general, two- dimensionally-laid warehouse.

CONSTITUTION: Product names of stored products, inventory quantity, and warehousing date for each address, and standard working quantity for each delivery port are stored in an inventory file 13 so that the standard working quantity of corresponding address is corrected at every renewal of inventory quantity of each address in the inventory file 13 based on parameters stored in a standard working quantity parameter memory 14. When delivery instruction for specifying the product name and delivery quantity is input from the outside, a work traffic line whose warehousing date is old and which is a result of multiplying a standard working quantity by delivery quantity is calculated for every delivery port so as to determine the address and delivery port where work traffic line becomes the lowest. The inventory quantity of the corresponding address in the file 13 is renewed based on the determined order information.