To obtain a new optically active carboxylic acid derivative useful as an optical resolution, agent of a racemic amine derived from a trans-1,2- cyclohexane-1,2-dicarboxylic acid anhydride as a starting raw material.

This optical resolution agent is an optically active 2- aminocyclohexane carboxylic acid derivative of formula I (R is an alkyl, aralkyl or arylsulfonyl capable of having a substituted group or a cyclic aliphatic acyl capable of having a substituted group; * exhibits an unsaturated carbon atom), e.g. trans-2-acetamide cyclohexane carboxylic acid. The compound of the formula I is obtained by affecting a concentrated ammonium to a trans-1,2- cyclohexane dicarboxylic acid anhydride, reacting with sodium hydroxide to form a compound of formula II, reacting with sodium hypochlorite to form a compound of formula III, further reacting with an acid anhydride or an acid chloride to form a compound of formula IV, then neutralizing with hydrochloric acid to form a compound of formula V and at last subjecting to optical resolution.