High sensitivity is an important index of an accelerometer for seismic monitoring. In this paper, we have designed a new
fiber Bragg grating accelerometer and, a theoretical structure is given. The theoretical analysis of the sensor is
established, and the results show that the sensitivity of accelerometer device is 2131.5pm/g and resonance frequency is
28.01Hz theoretically. It has a higher precision than traditional accelerometer on magnitude. In the experiment, we have
found that the output will react as a cosine signal while the input is a cosine signal. It indicates that the sensor has a good
linear relationship between output and response. We demonstrated a strain sensing test of measuring central wavelength
shifting by fiber Bragg grating.