Disclosed is a communication network management system for converting action parameters contained in abstract requirements (abstract policy information) regarding a network to parameters conforming to the network technology (ATM, SDH, WDM, etc.) and type of network element to be set, and setting these parameters in the element. Specifically, a policy administration portion converts action parameters contained in abstract policy information to parameters dependent upon network technology and a policy enforcement portion converts the parameters obtained by this conversion to parameters dependent upon type of network element to be set and sets these parameters in the element.