Lysine is the necessary amino acid for the animal but which can not be synthesized by themselves. Therefore, it is called “the most restrained amino acid” L-lysine monohydrochloride is a kind of feed additives which is made from corn starch and other raw materials. The producing of L-lysine monohydrochloride depends on bioengineering principle through the processing of liquid deep-level fermentation and refining. This product contains a wealth of nutritional amino acid, protein, vitamins, betaine and protein meal. It also contains a large number of inorganic salts which can make the animals to largely assimilate and metabolize protein in the feed, and can intensify and increase the nutrition in the feed, as well as promote digestion and assimilation. At the same time, it has the features of promoting animals’ growth rate, and strengthening abilities of anti-illness. It is the ideal product among the current feed additives, and has been wildly used in different kinds of mixed feed.