Abstract: The combine of Raman fiber amplification technique with wavelength modulation technique was reported in this paper. The near-infrared laser was amplified by Raman amplifier and was used for the long-distance remote detection of nature gas pipeline leak. Raman fiber amplifier performance was tested at 1650nm band, We found that the modulation frequency of seed laser was greater than 0.158×Pout-0.8 in order to ensure the output signal has no deformation when the output of Raman fiber amplifier was Pout.On this basis, 500m long distance remote detection was realized. And this experiment prepared the basis for next step air-borne detection of nature gas pipeline leak.

Key words: TDLAS