In this paper, the principle of fiber laser hydrophone was presented, and the development of fiber laser hydrophone was described. Researches on fiber laser hydrophone technology of our group were reviewed. It contains technologies on fiber laser hydrophone, fiber laser vector hydrophone, hydrophone array, field tests and application areas. The static pressure sensitivity of fiber laser hydrophone is better than－140 dB re 1 pm/μPa, from 20 Hz to 2000 Hz. The diameter of towed array is thinner than 30 mm, and the number of its elements is up to 64. Fiber laser hydrophone technology is coming into application from laboratory. We believe that the researches on practical application are of great importance.