Abstract: The volatile compounds in the muscle of Penaeus vannamei were determined by headspace solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) based on retention index (RI). Cluster analysis, correlation analysis and principal component analysis (PCA) were used to study the changes of volatile compounds. 66 kinds of volatile components during storage at 4℃ were detected. Cluster analysis indicated that the change of volatile components could be used to represent the change of freshness. Correlation analysis results demonstrated that 29 volatile components including 3-Methylbutanal, 2-Methylbutanal and pyrazine were significantly correlated with the freshness. PCA results showed that the characteristic volatile components of the samples stored for 0 to 7 days were guanidine, 2-ethylhexanol, 2-nonanone, etc. For stored samples during 8 to 12 days, the characteristic volatile compounds were pyrazine, 2-ethylhexanol, phenylethyl alcohol, etc. Characteristic volatile components during the entire storage period were pyrazine, 2-ethylhexanol, guanidine, etc, these volatile components could be applied to detect freshness of Penaeus vannamei.