Glucosamine and galactosamine are amino sugars that are found in acetyl forms in biological materials such as bacterial cell walls, insect and crustacean outer coverings, and human red blood antigens. They are also components of supplements for athletes and arthritis patients. Here we describe a method to analyze glucosamine, galactosamine, and β-alanine with the L-8900 Hitachi Amino Acid Analyzer.