A drum-type skeleton base structure of fiber Bragg grating(FBG) vibration sensor is designed,where the FBG is mounted on double cylindrical rings,and the structure consists of a number of flexible sheets.The FBG vibration sensor demodulation system uses phase modulation for demodulating.The experimental results shows that the resonant frequency of the developed FBG vibration sensor is 440 Hz,and the acceleration sensitivity is about 76.4 pm/g.The sensor adopts the double cylinder elastic rings for transverse vibration restraint and then its amplitude-frequency characteristics in the 20-300 Hz frequency range show a flat horizontal line,and the phase-frequency characteristics also show a flat horizontal line at phase angle of φ=0.The proposed sensor is suitable for the low-frequency(20-300 Hz) vibration signal detection.