A license management system for software which drives a single computer or a plurality of computers includes: an application program for requesting a decision of the number of license which it needs to drive itself and for receiving issuance of the license; a number of license decision unit for determining the necessary number of licenses in accordance with the request from the application program; and a license management unit for issuing the number of licenses which was determined by the number of license decision unit. Further, the number of license decision unit has means for determining the number of licenses based on the following multi-nominal function, LK=f (x1, x2, . . . , xn), where, LK is the number of licenses, and x1 to xn are parameters which are needed to determine the number of licenses. According to the present invention, it is possible to provide a license management system enabling issuance of a license in which the sales strategy of a software maker was considered.