The present invention relates to a composition for skin penetration, wherein the composition contains an ion conjugate in which a cationic compound is ionically combined with an anionic bioactive material, and delivers the bioactive material into the skin. According to the present invention, various kinds of anionic bioactive materials, such as diagnostic reagents, medicines, and fluorescent materials, are allowed to easily pass through cell membranes and skin layers, and thus can be delivered to the epidermal layer and dermal layer of the skin.
