Regarding the present situation of different types of sensors being used in real-time monitoring building structure and its working environment, a general demodulation system for fiber Fabry-Perot sensor and fiber Bragg grating sensor based on fiber Fabry-Perot tunable filter was described. The structure of this system and its principle of demodulating these fiber sensors were studied. The experiment shows that this system can demodulate these fiber sensors accurately and effectively, and it also have a multiplexing capability. The demo-dulation accuracy of fiber Fabry-Perot sensor is under ２ με, and the demodulation accuracy of fiber Bragg grating sensor is under 0.5 με.