ZigBee’s tree topology shows better performance in reliability and power consumption than star and mesh topologies in network layer.However,the command and data packets may be inconsistent in tree structure under potential attacking situation.The proposal model which is used by signal-power-comparison method can add parent-child node automatically to form tree topology and transport data packets successfully.Simulation results show that the model can effectively solve confliction between command and data packets,and provide integrate and expandable flow from topology building to data transmitting.