Abstract:To investigate the liposoluble constituent and determinate the contents of 21 kinds of free and hy－ drolyzed amino acids in chia seeds by pre-column derivatization reversed phase high-performance liquid chro－ matography（RP-HPLC）. The liposoluble constituent in samples were identified and determined by gas chrom－ tography-mass spectrometry （GC-MS）. The samples were derived with phenyl isothiocyanate and detected by RP-HPLC. The contents of 21 kinds of free and hydrolyzed amino acids in chia seeds were determined by gradi－ ent elution chromatography at the wavelength 254 nm. Fourteen compounds were separated in the liposoluble constituent of chia seeds， and the content of linolenic acid could up to 83.41 %. There was a good linear rela－ tionship of the 21 kinds of amino acids in the range of 0.0050 mmol/L -3.2500 mmol/L （the coefficients of cor－ relation were all over 0.9990）. The average recoveries of 21 kinds of free amino acids were 93.68 %-102.36 % （RSD=0.91 %-2.76 %， n=6）； while the average recoveries of 21 kinds of hydrolyzed amino acids were 94.86 %-105.73 % （RSD=0.75 %-2.83 %， n=6）. The main component in the liposoluble constituent of chia seeds was unsaturated fatty acid， while the content of O-mega3-linolenic acid was hightest. The methodology validation showed that the method of pre-column derivatization RP-HPLC was suitable for determination of free and hy－ drolyzed amino acids in chia seeds.