There are many uses of amino acids. They are used as nutrition supplement for humans and animals. Proteins are metabolized constantly in the body and most of the amino acids absorbed are used to replace body proteins. Foods and feed from plant proteins lacking in some essential amino acids are fortified with their addition. L-lysine and DL-methionine are widely used as feed improvers. They are used for flavor and taste enhancement in foods. Some are very sweet; for example glycine is as sweet as sugar and is sometimes used in soft drinks and soups. Glycine is present in large amounts in shrimps to which it confers its sweet taste. The peptide, L-aspartyl-L-phenylalanine methyl ester is particularly sweet. The most common application of amino acids in medicine is in transfusions administered when the oral consumption of proteinaceous food is not possible. In the industry they are used as surface-active agents, production of polymers and manufacture of cosmetics. This chapter discusses methods for amino acid production by semi-fermentation, enzymatic process and by direct fermentation; and production of glutamic acid as representative amino acid. Fermentor procedure, raw materials, production strains and downstream processing for amino acid production are also discussed.