An object of the invention is to provide a novel arginine derivative and a cosmetic satisfactory in compatibility with the skin and hair, excellent in skin softening effect and skin-conditioning effect, and satisfactory in use feeling with little sticky feeling and tense feeling.Such present invention relates to an arginine derivative represented by the following general formula (1):wherein R1 and R2 are a hydrogen atom or a linear or branched monohydroxyalkyl group having 2 to 3 carbon atoms and at least one of R1 and R2 represents a linear or branched monohydroxyalkyl group having 2 to 3 carbon atoms and R3 represents a hydrogen atom, an alkali metal atom, an ammonium, or an organic ammonium, and a cosmetic containing the same mixed therein.