YL Amino acid analyzer was developed to facilitate the determination of amino acids in protein hydrolysates or in native samples. There are two different method for amino acids analysis. The first method is UV/VIS detection with the use of Ninhydrin reagent, which react with both primary and secondary amino acids. The second method is Fluorescence detection with the use of o-phthalaldehyde(OPA), that gives greater sensitivity. Our amino acid analyzer using post-column derivatization method can analyze most of amino acids in protein hydrolysates (protein, collagen, peptides, and foods) as well as in native samples (physiologic fluids, tissue extracts, broths, musts feeds and beverages).