Abstract: Freshness of Litopenaeus vannamei changed， which gave out unpleasant smell， and its smell was respectively detected with the electronic nose and HS\|SPME\|GC\|MS， combined with the sensory evaluation and TVBN. The results showed that the output of five sensors of electronic nose， which was consisted of six sensors， presenting regular change. The volatile components in prawn were extracted by solid phase micro\|extraction （SPME） and determined by gas chromatography\|mass spectrometry （GC\|MS）.The volatile components in prawn were nitrogenous and sulfur compounds， alcohols and inflammable gas. Compared the change rule of output of each sensor of electronic nose with the detected results of volatile components， the two test results were better consistent. It has proved that the electronic nose could be tried to assess freshness of prawn.

Key words: Litopenaeus vannamei, freshness, smell