PURPOSE: An external use skin composition containing horse placenta extract or horse milk is provided to suppress melanogenesis and to ensure skin whitening and moisturizing. CONSTITUTION: An external use skin composition for skin whitening contains 0.001-10.0 wt% of horse placenta extract or horse milk as an active ingredient. The composition is a cosmetic composition. The cosmetic composition is manufactured in the form of an emulsion, lotion, cream, solution, suspension, anhydrous product(oils and glycols), gel, mask, pack, and powder. The cosmetic composition contains acceptable carriers such as alcohol, oil, surfactant, fatty acid, silicon oil, wetting agent, moisturizing agent, stabilizing agent, UV protecting agent, or perfume.본 발명은 말 태반을 단백분해효소로 가수분해하여 얻어진 추출물 및 마유 중 하나 이상을 포함하는 피부 미백용 또는 피부 보습용 피부 외용제 조성물을 개시한다.