Real-time monitoring of vibration properties in micro-seismic applications, such as petroleum exploration, physical oceanography, and perimeter security, is important for deep exploration and the prediction of geological disasters and other fields. The fiber Bragg grating (FBG) vibration sensor with symmetrical V-shaped flexible hinges and a dual mass block is proposed. Utilizing formula derivation and simulation software, the sensor's structural parameters are optimized and subjected to analysis. These simulations inform the fabrication of the actual sensor, and subsequently, the sensor's performance is empirically tested. The results show an average sensitivity of 73.86 pm/G and a natural frequency of 800 Hz, with a working range of 20–340 Hz. Its exhibits anti-interference in the transverse direction is less than 5 % during vibration measurement. The research outcomes offer a point of guidance for the progress of FBG accelerometer development within applications that involve measuring low- to medium-frequency accelerations.