Abstract: As the core equipment of the power system, the temperature monitoring of the windings of thermal power generators is crucial for ensuring the safety and stable operation of the equipment. However, in practical applications, traditional temperature monitoring technologies, especially in high electromagnetic and high-temperature environments, often face many limitations and are difficult to fully meet the monitoring requirements of modern thermal power generators. In recent years, optical fiber temperature sensing technology has achieved rapid development, especially sensors which fiber Bragg gratings sensors exhibit outstanding application potential. This paper focuses on the working principle and layout methods of optical fiber temperature sensors. By scientifically and reasonably laying out sensors and combining with efficient signal demodulation systems, the real-time performance is greatly enhanced, and synchronous temperature monitoring of multiple monitoring points can be achieved. In the temperature monitoring of rotor windings, the temperature of specific points can also be accurately located, significantly improving the accuracy of temperature measurement. Although optical fiber temperature sensing technology has many advantages, it still faces some challenges in practical applications, such as grating drift, aging, and external interference. Compared with traditional technologies, optical fiber temperature sensing technology is still more competitive and will play an increasingly important role in intelligent power plants and digital power grids.