Abstract: Considering the inherent defections of IP protocol family such as absence of discipline, the demands of regular IP technology based military communication core network on precise QoS guarantee, service type distinction, agile resource arrangement, and rapid feature updating can hardly be met. An SDN based military communication core network architecture is introduced, functionality and mutual relationship of components of the architecture is analyzed, working flow of resource assurance in SDN based military communication core network is described. Network ensurance capability of SDN architecture is verified utilizing open-source SDN controller. Characterized by separation of forward plane and control plane, control centralization, and interface opening, SDN architecture can manage to handle the feature demands of military communication core network.