Provided is a method for improving the retention properties of a compound in the skin, which is effective for prevention of aging or improvement of the skin. An external preparation for the skin in an oil-gel form according to the present invention, which contains (1) a compound represented by general formula (1), an isomer thereof and/or a pharmacologically acceptable salt of the compound or isomer, and (2) a partially crosslinked methyl polysiloxane, enables easy migration of the above-described active ingredient (1) into the skin from the preparation, while enhancing the cutaneous absorption and improving the retention properties in the skin. (In the formula, R1 represents a linear or branched alkyl group having 1-4 carbon atoms and substituted by a carboxyl group, or a linear or branched alkyl group having 1-4 carbon atoms and substituted by a carboxylic acid ester group having an alkyl chain with 1-4 carbon atoms； and each of R2 and R3 independently represents a linear or branched alkyl group having 1-4 carbon atoms.)
