To find a substance which has a skin cosmeticizing effect such as prevention of skin aging, amelioriation of sensitive skin, or antipruritic action, and can serve as an effective ingredient for a hair-care product, thereby providing cosmetics comprising the effective ingredient. Concretely, there are provided cosmetics characterized in that the cosmetics comprise as an effective ingredient a compound selected from a fucoidan, a degradation product thereof, a sulfated monosaccharide or a salt thereof.