Abstract: The wireless sensor network(WSN) is a typical networked embedded system.It involves in both embedded systems and networks,and is extraordinarily application-specific;therefore testing and debugging WSN becomes relatively complicated with various difficulties.Developing a "one-fits-all" platform for WSN testing and debugging is difficult to achieve.In order to efficiently test and debug the implementation of WSN application,this paper carefully analyzed previous related researches,adopted the half-practicality simulation strategy, proposed a hybrid testing and debugging system for WSN, and solved the problems that pure software simulation veils too many hardware implementation details and in-situ platforms can only provide limited visibility and controllability for both the embedded systems and the networks, thus achieved a balanced achievement.At last, an instance platform of the hybrid testing and debugging system for WSN was implemented in the field programmable gate array (FPGA);experimental results verified the correctness and validity of the proposed system.