A process for producing 3-formyl-5-trifluoromethylbenzonitrile which comprises a first step in which a 3-dihalogenomethylbenzotrifluoride represented by the general formula [1]: [Chemical formula 12] [1] [wherein X and Y represent the same or different halogeno (fluorine, chlorine, bromine, or iodine)] is brominated to obtain a 1-bromo-3-dihalogenomethyl-5-trifluoromethylbenzene represented by the general formula [2]: [Chemical formula 13] [2] [wherein X and Y represent the same or different halogeno (fluorine, chlorine, bromine, or iodine)], a second step in which the 1-bromo-3-dihalogenomethyl-5-trifluoromethylbenzene is hydrolyzed to obtain 1-bromo-3-formyl-5-trifluoromethylbenzene, and a third step in which the 1-bromo-3-formyl-5-trifluoromethylbenzene is cyanated with a cyano compound to obtain 3-formyl-5-trifluoromethylbenzonitrile.