A method for preparing an ester bleach activator compound is disclosed. The method includes (A) preparing fatty acid monoester; (B) making chloroformate by reacting the fatty acid monoester with at least one selected from the group consisting of phosgene, diphosgene and triphosgene in the presence of base; and (C) reacting the chloroformate with hydroxybenzene, its derivatives, or its salts in solvent. According to the method, the ester bleach activator compound can be made in a simple and economic way.