PURPOSE: To obtain a new sterol derivative capable of imparting moisture holding ability to a horny layer of the skin and the moistness to the skin, having improving and preventing effects on skin roughening and useful as cosmetics, toiletry products and medicinal bases.

CONSTITUTION: Natural sterols such as cholesterol, stigmasterol, sitosterol, lanosterol or ergosterol and a dicarboxylic acid (diester) expressed by formula I [R2 is expressed by the formula (CH2)n n is an integer of 1-10); R4 is H or 1-5C alkyl] or a dicarboxylic acid anhydride expressed by formula II (e.g. succinic anhydride) are thermally refluxed in the presence of p-toluenesulfonic acid monohydrate in a solvent such as xylene and the reaction is carried out for 3hr while subjecting the produced water, etc., with xylene to the azeotropic distillation and removing the water with a trap. The solvent is then distilled away from the reactional mixture and cooled. Ethanol is subsequently added and the deposited precipitate is collected by filtration to afford the objective sterol derivative expressed by formula III [R1 is (hydrogenated) natural sterol residue].