The present invention relates to a process for producing an optically active .alpha.-fluorocarboxylate derivative represented by the formula [2], ##STR00001## by reacting an optically active .alpha.-hydroxycarboxylate derivative with trifluoromethanesulfonyl fluoride (CF.sub.3SO.sub.2F) in the presence of an organic base, in the formula [2], R represents a straight-chain or branched-chain alkyl group of a carbon number of 1 to 12; one of or two by any combination of aromatic hydrocarbon groups, unsaturated hydrocarbon groups, straight-chain or branched alkoxy groups of a carbon number of 1 to 6, aryloxy groups, halogen atoms (fluorine, chlorine, bromine and iodine), protected carboxyl groups, protected amino groups or protected hydroxyl group can be substituted on any carbon atoms of the alkyl group; R.sup.1 represents a straight-chain or branched-chain alkyl group of a carbon number of 1 to 8; any carbon atoms of the alkyl groups of R and R.sup.1 may form a covalent bond; and * represents an asymmetric carbon.