Due to tanks moving, joining and leaving, the wireless network topology formed by them will continuously change. Hence, how to make moving tanks to form a smart networking system is an important research issue. Moreover, the information exchange between nodes in a networking system can be performed via a multicast tree structure, and the root node can collect information from all the nodes in the structure. So in this paper, an algorithm is proposed to build an efficient distributed multicast tree construction algorithm for a mobile network. Such a multicast tree can be continually adjusted according to the latest topology information carried on message packets propagated among nodes. In addition, in all possible routing paths, a path with the lowest weight will be dynamically selected to improve the overall system messaging throughput. The above technique can be applied to make military vehicles form a smart networking system, including tanks, armored vehicles and transport vehicles, etc. Furthermore, through this network, the fast-changing situation of the battle can be immediately sent back to the server for the commander to refer to.