Abstract: The software-defined command and control system pays more attention to the need for the independent adaptation of the command and control system. Aiming at the problems that the traditional characterization methods can not reflect the complex network relationship among tasks, resources and capabilities in the software defined command and control system, a "three layers and six nets" hypernetwork characterization method of software defined command and control system and the corresponding hypernetwork parameters are proposed; the measurement methods of different types of edges in the resource information flow kill chain are analyzed; the key kill chain searching method of the resource information flow network based on two stages and edge weights is proposed, and the case verifications are carried out. This method provides technical support for the key kill chain searching and assistant command personnel in decision-making in the software-defined command and control system.