A quasi-distributed fiber optic sensor network based on fiber Bragg grating(FBG) sensor is proposed in order to solve the problems of complicated sensor wiring and fast sensor degradation of the traditional health monitoring methods for large elevator steel frame structure. First, the basic principles of FBG stress and temperature sensors are presented, and the overall scheme of FBG remote sensing and monitoring system with elevator steel frame structure by the method of “space division multiplexing + WDM” is constructed, the strain and displacement sensor array are designed, and the demodulation algorithm of FBG strain gauge and FBG displacement meter are investigated. Then, the actual model of the elevator steel frame structure was used to build the corresponding test system, the FBG strain gauge and FBG displacement meter are installed to test the distributed network, and the supporting health condition monitoring software of the elevator rigid structure is developed. The test results show that the proposed system can respond in real time with good stability. The system provides real-time monitoring data and safety warning functions for the safe operation of outdoor large vertical and diagonal elevators, and can provide big data support for “on-demand maintenance”.