The cantilever beam vibration sensors are studied in this paper. it mainly expounds The working principle and theoretical analysis of the sensor are described, and the experimental study on the amplitude frequency characteristics and sensitivity of the sensor has been carried out. The experimental results show that the natural frequency of the vibration sensor is 90 Hz, the sensitivity of the sensor is as high as 121 pm/g (g=9.8 m/s2, which is the acceleration of gravity), and the flat area is 10 to 50 Hz. The vibration sensor has good frequency response in low frequency range. Finally, the fatigue analysis and optimization of the cantilever beam of the sensor are carried out, and the fatigue life of cantilever beam is increased by 150%。