To provide a skin external preparation which has high humectancy, skin elasticity and is safe.

The skin external preparation comprises hyaluronic acid or its salt and a seaweed extract. The seaweed extract is preferably the one obtained by extracting brown algae such as Hizikia fusiforme, sargassos, Eisenia bicyclis, wakame seaweed, giant kelp, and Fucus vesiculosus with water or water and a hydrophilic organic solvent, and furthermore the skin external preparation which additionally comprises any one of glycyrrhizic acid, its derivative and its salt, and maltitol is more effective.