To achieve real-time monitoring and evaluation of the structural health status of solid rocket motors (SRMs), a high-strength femtosecond grating sensing network was designed and developed. The sensors were coated and packaged, and SRM interface debonding simulation experiments were conducted. A simulation demonstration system for SRM strain, temperature, and load was designed. A digital twin model of the engine based on the data collected by the optical fiber sensor was established, and an accurate mapping between the real SRM and the digital twin was formed. Finally, the optical fiber sensor array was implanted in the SRM, and water pressure monitoring experiments, high-and low-temperature storage experiments, long-term monitoring experiments, and ignition tests were conducted on the SRM. Non-destructive testing conducted verification experiments on the monitoring results. The research results indicate that the sensor network can accurately measure the strain state of the SRM, providing effective data support for its structural health management.