Abstract: The reaction between amino acid and malondialdehyde (MDA) was studied by fluorescence spectroscopy.The effect of time, pH and concentration on the emission spectroscopy of lysine-MDA system was researched, and the reaction charactertic of 19 kinds of amino acid with MDA was compared.The result showed the product of AA-MDA system had Ex.400nm and Em.460nm, easier to happen under the neutral condition, with the reaction time prolonged, the fluorescence product increased.The concentration of MDA was much more than that of lysine, more fluorescence product increasing.The fluorescence intensity had significant difference among kinds of AA-MDA.Arginine, lysine, histidine and glycine could easier react with MDA to produce fluorescence product, while proline, hydroxyproline and tryptophan could not.