The FGB-STN type fiber Bragg grating surface strain sensor has a wide range of stress-strain monitoring applications, such as Bridges, DAMS, large steel structure buildings, etc. It can also be used for tunnel wall deformation monitoring, etc. The dual grating packaging structure can achieve self-compensation for temperature, is convenient for calculation, and can be connected in series with multiple or other types of fiber Bragg grating sensors for real-time monitoring.