One of the final research goals for smart structures is to integrate sensing elements with composite materials. It is the most potential technical approach that the standardization and modularization of fiber optic smart layer system with function of self-diagnosing is designed. The fiber grating smart layer (FGSL) with embedded fiber Bragg grating (FBG) sensors is fabricated using dielectric substrate of polyimide. The calibration test of embedded FBG sensors is conducted and the models of strain measurements and temperature measurements for FBG sensors embedded inside FGSL are set up. The experimental results show that the wavelength shift of Bragg grating is excellently linear with strain and temperature by embedded FBG sensors, but it is noted that the thermal characterization of the structure built-in FGSL should be investigated. The active and real time monitoring system would be established by fiber Bragg grating networks embedded inside FGSL and advanced information treatment technology.