Study on fatty acid composition of commercially available samples pomegranate seed oil. Through esterification reaction, using hexane as solvent direct injection and quantified by internal standard C11∶〖KG-*2〗0 methyl ester. Gas chromatography-mass spectrometry was used for analysis of fatty acid methyl ester, and NIST library search to identify various components. The results showed that punicic acid were the main fatty acids in the sample which content more than 70%(w/w). This method is simple and fast, the analytic time is short and the result is accurate, which can provide reference for the similar products of fatty acid content.