This paper puts forward a pole-rod type of fiber grating strain sensor,and the theory research and sensor calibration experiment are conducted.The elastic system is composed of cantilever beam,sticking the optical fiber on the cone hole of cantilever beam and using the levers of transfer the monitor the object surface strain.The experimental results show that the strain sensor has high sensitivity,good linearity and repeatability.The strain sensitivity is 1 pm/με.with linearity of 0.994 and the temperature sensitivity is 16 pm/℃ with linearity of 0.996.It can be applied to the strain measurement of high precision demand.