A miniaturized, wide-band, high-sensitivity fiber Bragg grating (FBG) vibration sensor is proposed. The millimeter-scale FBG is used to design the sensor structure. The "lever hinge" structure is used as the strain transfer beam, and the center of gravity of the entire mass block is adjusted by hollowing out the end of the mass block, which improved the natural frequency of the sensor. This structure increases the natural frequency of the sensor with a slight decrease in sensitivity. In this study, a vibration sensor with a volume of 15 mm × 15 mm × 15 mm is designed to satisfy the miniaturization requirements of sensors on space cameras, and structural design and finite element simulation analysis were performed. The structural optimization of the sensor is completed, considering the working frequency band and sensitivity. The sensor is fabricated by millimeter FBG writing and sensor packaging. A vibration test system is built to test and analyze the characteristics of the sensor. The results show that the natural frequency of the sensor is approximately 1250 Hz, the sensitivity exceeds 83.3 pm·g^-1 when the excitation frequency is 750 Hz, the lateral anti-interference ability of the sensor is excellent, and the cross-sensitivity is lower than 4%.