An improved bridge Fiber Bragg Grating (FBG) temperature sensor technology is presented in this paper. The sensitivity and stability of the material and structure on the wavelength of the FBG are studied theoretically and experimentally. Compared with the traditional bridge temperature monitoring technology, the new sensor technology can adapt to a low-temperature environment and has high resolution. In order to verify the technology, experimental verification is carried out on the basis of theoretical analysis. The results show that the sensitivity of the new optical fiber temperature sensor is about 22 pm/°C, twice that of the bare raster, and shows good stability.