Optical fiber sensing technology shows broad application prospects in industrial monitoring, health detection and other fields with its significant advantages of anti electromagnetic interference, small size and easy reuse. Fiber Bragg grating sensing technology has the unique characteristics of high sensitivity of multi parameters, fast response speed and strong local measurement ability, which has excellent performance in high-precision multi-parameter monitoring. In recent years, thanks to the breakthroughs in key technologies such as on-line preparation of wire drawing tower and femtosecond laser direct writing, a single fiber can realize the high consistency industrial preparation of tens of thousands or even hundreds of thousands of gratings. Combined with the large-capacity distributed demodulation method and multi-parameter networking mechanism, people have successfully constructed a large-scale grating array sensor network suitable for long-distance, large-scale and complex environments. This paper systematically summarizes the preparation process, demodulation mechanism, network architecture and typical applications of grating array fiber, including the health monitoring of large engineering structures such as highways, subways and airport runways, as well as innovative applications in perimeter security, underwater acoustic detection, power cable fire warning and other fields, and focuses on the real-time processing methods of large-scale data. The research shows that the sustainable development of large-scale grating array optical fiber sensor network will promote the transformation of infrastructure and large equipment health monitoring mode from passive response to active prevention, and provide a solid sensing foundation for the operation of a new generation of intelligent infrastructure.