The present invention provides a compound selectively activating PPAR.alpha., which is useful as a medicament. The present invention is specifically directed to a benzoic acid derivative represented by the following general formula (1): ##STR00001## wherein A represents an oxygen atom, a nitrogen atom, or a sulfur atom; R represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkyl-alkyl group, an aryl group, an aryl-alkyl group an aryl-oxy-alkyl group, a pyridyl-alkyl group, an alkoxycarbonyl-alkyl group, or a carboxy-alkyl group; X represents an oxygen atom, an NH group, or an S(O).sub.n group (wherein n represents an integer of 0, 1, or 2); and m represents an integer from 2 to 8; or a salt thereof. The present invention also provides a medicament comprising the benzoic acid derivative or the salt thereof as an active ingredient.