Micro seismic monitoring technologies based on fiber laser sensors were introduced. Owing to the characteristics of narrow line width, low noise, fiber laser sensing can achieve high sensitivity and low system noise through some methods, such as enhance-sensitivity packaging, interferometric demodulation technology. With the advantages of small in size, resistant to high temperature and pressure, and easy to be wavelength division multiplexing, it is very fit for micro seismic monitoring. The principles of fiber laser hydrophone and fiber laser accelerometer were described. Some factual application examples of using these fiber laser sensors for micro seismic monitoring were presented.