Provided are an anti-inflammatory agent containing, as an active ingredient, at least one selected from amino acid derivatives represented by formula (I) ##STR1## wherein Ar represents an optionally substituted 2-hydroxyaryl group, n is 0 or 1, R.sup.2 represents a hydrogen atom or a side chain of an .alpha.-amino acid or .beta.-amino acid, X represents --O-- or --NH--, R.sup.1 represents a hydrogen atom or a group that forms, together with R.sup.2 and an adjacent atoms, a cyclic structure of pyroglutamic acid, and R.sup.3 represents a hydrogen atom, an alkyl group having from 1 to 22 carbon atoms or an alkenyl group having from 2 to 22 carbon atoms, and salts thereof, and toiletries or skin external products containing the same. The anti-inflammatory agent of the invention inhibits expression of an inflammatory protein and activation of a gene transcription control factor that participates therein, and exhibits a good feeling upon use and a safety.