Abstract: For improving the reliability of the optic fiber selfdiagnosing system, a Fiber Bragg Grating sensor network which is applied to monitor the strain distribution of a certain aircraft wing box is researched. Considering the sensor arrangement, the optic fiber strain rosette is adopted in the monitoring point. Considering the network connecting type, the optical switch and the adjacent matrix of the graph theory is adopted to connect the demodulation equipment for the disabled sensor signal in a different path once more, thus the disabled sensor signal can be demodulated again in the optic fiber sensor network. The research results indicate that if one or more sensor signals in the optic fiber network system disabled simultaneously, depending on the healthy Fiber Bragg Grating sensor in the damaged regions, the adjacent matrix of the graph theory combining with the faulttolerant technique can be adopted to achieve the selfrecovery of the selfdiagnosing sensor network without damaging the structure.