Abstract: In order to study the influence of L-alanine on the flavor of fish sauce,evaluation of the effect of L-alanine on improving the taste and decreasing the stench smell of fish sauce by means of sensory evaluation. Changes in the volatile flavor compounds of fish sauce treated with L-alanine were analyzed by headspace solid phase microextraction(HS-SPME)coupled to gas chromatography-mass spectrometry(GC-MS). The results showed that the addition of L-alanine(0.5%~2.0%)could increase the sweetness,improve the delicacy and decreased the stench smell of fish sauce. Moreover,the analysis indicated that the addition of L-alanine could decrease the volatilization of sulfur compounds to a certain extent,thus reducing its unpleasant smell and improving the flavor of fish sauce. This study would provide a useful reference for L-alanine on improving the flavor quality of some seafood.