An efficient and practical method for the preparation of 4-nitrogen-substituted benzoic acids is described. Our method consists of the aromatic substitution of 2,2,2,4'-tetrafluoroaceto-phenone with amines, followed by haloform reaction to the benzoic acids. In this method, even though for the less nucleophilic 7-, 8-, and 9-membered amines 1 equiv. was used, corresponding benzoic acids were obtained in moderate to excellent yield. As the experimental procedure including purification is simple, this method is applicable to large-scale syntheses.