Safety monitoring is crucial during the construction of building projects. This paper proposes a safety monitoring system based on fiber Bragg grating (FBG) sensors and it can effectively monitor some key safety parameters during the construction process. The monitoring system was applied to actual construction projects for testing, and safety parameters such as displacement, inclination, strain, and earth pressure were monitored in real-time. The test results show that during the construction process, the system can achieve real-time and accurate monitoring of safety data, effectively avoiding the occurrence of safety accidents, and the application effect is very significant.