L-(-)-Lysine monohydrochloride is widely used in the food industry as a nutritional supplement to enhance the protein content in various products, particularly in cereals and baked goods. It is also added to animal feed to promote growth and improve overall health in livestock.

In the pharmaceutical sector, it serves as a key ingredient in medications aimed at treating and preventing lysine deficiency, which can lead to various health issues. It is also utilized in the formulation of dietary supplements to support immune function and aid in the absorption of calcium, contributing to bone health.

Additionally, L-(-)-Lysine monohydrochloride is employed in cosmetic products for its role in collagen synthesis, helping to maintain skin elasticity and reduce signs of aging. Its applications extend to research laboratories where it is used as a reagent in biochemical studies and protein synthesis experiments.