ABSTRACT A high sensitive fiber Bragg grating (FBG) acceleration sensor based on filtering demodulation is analyzed on sensitivity, resolution and temperature experiment. Sensitivity and resolution of FBG sensor lies on the structure of the sensor shell and the shape of the reflec tivity spectrum of FBG. The temperature ex periments of the FBG sensor show the work and storing temperature range of the sensor based on different preparing stress and packaging glue. Experiments on the detecting system’s frequency character have been done. Results show that this acceleration sensor can detect the smallest acceleration of 1mm/s 2 with a flat response from 5Hz to 40Hz. Keywords: FBG, sensitivity, high temperature, low temperat ure, acceleration, sensor, modulation, experiment 1. INTRODUCTION In recent years, significant progresses have been gotten in the field of fiber- optic acceleration sensors. There has been considerable interest devoted in fiber-optic acceleration sensors because they afford all the advantages inherent with fiber optic sensors. Various types of fiber-op tic acceleration sensors have been widely used in fields of oil well logging, inertial navigation systems, earthquake monitoring, micro-seis mic monitoring and forecast of rock layer movement. So far, the fiber-optic acceleratio n sensors with high sensitivity, wide dynami c range, high resolution and compact size are urgently required. As a research aspect towards this direction, many kinds of fiber-optic acceleration sensors have been proposed