To reduce the disturbance of acceleration effects on distributed feedback fiber laser hydrophone used in underwater sound detection, one symmetric structure with two diaphragms was designed and its anti-acceleration performance is investigated. The theoretical acceleration sensitivity model of the hydrophone with two diaphragms was established. After the relation between acceleration sensitivity and component size、materials parameters were analyzed, the structure of the hydrophone was optimized. Prototype of the hydrophone was fabricated and tested. The average pressure sensitivity reaches －132.6 dB with the fluctuation less than ±0.5 dB in the frequency range of 2.5～10 kHz, while the acceleration sensitivity is less than －28 dB. The results show that this structure of hydrophone ensures the high pressure sensitivity and flat response curve, whose anti-acceleration performance is improved at the same time, which will greatly enhance the signal-to-noise ratio of the hydrophone in the moving state.