In the activities of the medicine logistics, statistics of in-&-out-of-storage management of drug has always been the emphasis and difficulty in management. The WMS system can play a key role, but for some pharmaceutical factories which are not willing to cooperate with the system, extra supervisors are necessary to deal with this problem. By considering with the adjustment of quantity and level of supervisors, this article finds a way to make the quantity of the inventory and outbound as accurate as possible, and provides certain scientific basis on developing more scientific and reasonable warehouse personnel arrangement.