To provide a method for producing a compound useful as a synthetic intermediate for new optically active 1,2-disubstituted-2,3-epoxypropanes having excellent herbicidal activities.

This method for producing the optically active 1,2- disubstituted-2,3-dihydroxypropanes represented by general formula (4) (wherein, A is a 2-substituted indane-1,3-dion-2-yl group or a haloalkyl group; and B is a benzene ring which may be substituted) is characterized in that (a) the 1,2-disubstituted-2,3-epoxypropanes represented by general formula (1) (wherein, A and B have the same meanings as defined before) is hydrolyzed in the presence of an inorganic acid or (b) the 1,2-disubstituted-2,3-epoxypropanes is subjected to a ring-opening reaction in the presence of a carboxylic acid, and the product is further subjected to solvolysis.