In order to obtain accurate parameters of the downhole environment in a large range and effectively suppress the noise, an optical fiber sensing internet of things system based on a new fiber Bragg grating(FBG) package was studied. A sensor module that can test strain and temperature simultaneously was designed. The new FBG package structure was trial-produced. An optical fiber stress monitoring distribution network conforming to the tunnel structure was built. A method based on cross-correlation difference calculation was used to eliminate vibration noise. The experiment continuously monitored the stress and temperature of the underground tunnel. The results show that the FBG at 45° and 60° in the arch can accurately record the stress and temperature change data. It can be seen that the system has higher stability and better adaptability in large-scale downhole environmental parameter monitoring.