Skin is the coating of all human and animal organisms. It is a kind of space where different processes take place. Skin is the largest and the heaviest organ in the body. Also, it is a barrier, that stops water and the part of body, which should be particularly protected . The skin is composed of three main layers: epidermis (Fig. 1), dermis (Fig. 3) and subcutaneous tissue (Fig. 5). Each of these layers has completely different role and is characterized by various properties. Epidermis is the outermost layer of skin. It consists of a living and a dead zone. The living area forms new cells which are the subject to further changes, while in the zone of dead cells they are highly flattened and devoid of nuclei . In the epidermis, exactly in the reproductive output layer there are melanocytes, which are cells responsible for production of the pigment - melanin (Fig. 2). Melanin is responsible for color of hair, eyes and skin. It is formed from tyrosine as a result of numerous biochemical reactions . Biological activity of melanin is determined by the presence of appropriate peptide. The sequences of its active components are: Ser-Tyr, Ser-Met-Glu-His-Phe-Arg, and Trp-Gly-Lys-Pro-Val. It is possible to protect the skin also against the solar radiation. The hormone MSH absorbs and reflects UV radiation. Under the influence of UV radiation the amount of melanin increases, causing temporary changes in skin color . Under the epidermis there is a proper skin, which is composed of elastic fibers, collagen fibers, and the basic substance, which fuses the fiber elements. The elastic fibers are scattered among collagen fibers. Proper skin is the place where a valuable protein - very important in cosmetics - occurs - the native collagen. It is the main protein of connective tissue. Collagen has a very high tensile strength and is a major component of tendons. It is responsible for skin elasticity. Loss of collagen from the skin causes wrinkles . A distinctive layer of skin is the subcutaneous tissue. It combines dermis with muscles. It is composed of fat cells separated by connective tissue. The size and the shape of fat cells vary depending on gender, diet and also age . Skin, like other authorities is aging. These process may be accelerated or delayed under the influence of various endogenous and exogenous elements (Tab. 1). Also genetic predisposition are of significant importance. It seems that, as soon as we age, we inherit from our ancestors. To delay the aging process, it is necessary to properly take care of and protect the skin. There are many ways to delay aging of the skin. The most successful, for example cosmetics with active ingredients such as peptides, will be presented here.