Cosmetics are very easily deteriorated due to microbial contamination in the process of production, storage and using. Spoiled cosmetics are especially harmful to human skin. ε- Polylysine has broad antibacterial spectrum, it can effectively inhibit the growth of microbes and ensure the good quality of products. ε- Polylysine is a polymer of amino acids, to be known as nutritional preservative, so it is much more environmentally and friendly, safe and efficient. ε- Polylysine has been widely applied in most of the daily chemical products such as toothpaste, gargle, soap, hand washing, wet wipes, kitchen cleaning agent, sanitary napkins, baby diapers.