PURPOSE: To reduce handling work and to increase the operation rate of a device by a method wherein a case emptied of its semiconductor product at the feeding side is caused to travel to the storing side and then the emptied case accommodates the processed semiconductor product at the storing side.

CONSTITUTION: A case 1 containing an unprocessed semiconductor product is set at a feeding side stock section 7. The stock section 7 then goes into work for the semiconductor product to be fed into the processing unit. The case 1 now an empty case 2 is placed on a transfer means 6. When necessary, a stage 3 causes the empty case 2 to revolve to set it at the storing side stock section 8 as an empty case 4. The empty case 4 now a case 5 set at the storing side stock section 8 houses the semiconductor product that has undergone processing.