In this paper, the networking architecture of wireless sensor system is studied and proposed by simulation analysis and experimental testing to implement the fault detection and reconfiguration mechanism on ZigBee network. The tool software NS2 is used to simulate and analyze the networking topologies and transmission characteristics for ZigBee network system. By way of simulation analysis of different networking topologies, the system performance of ZigBee sensor network is discussed and recognized individually for the mesh and tree routing algorithms, respectively. Moreover, the CC2430 development kit of Texas Instrument (TI) is used to develop the ZigBee nodes including the coordinator, router, and end-devices to form a specific application scenario for disaster prevention and warning system. By applying the Inter-PAN conception and algorithm, the networking architecture of ZigBee sensor system is proposed and exercised to carry out the fault detection and reconfiguration functions which may increase the reliability of data transmission on ZigBee network. Finally, through the various and practical experiments, the proposed networking topologies are implemented and tested to illustrate and evaluate the system feasibility and performance of proposed ZigBee network for wireless sensor system.