The invention discloses a method for preparing an iguratimod intermediate IV, which belongs to the technical field of medicine and chemical industry. The present invention replaces nitrobenzene with nitromethane as the preparation of Alamod intermediate IV (α-amino-2-methoxy-4-methanesulfonamido-5-phenoxyacetophenone hydrochloride ) solvent, the weight yield of the prepared Alamod intermediate IV can reach 102~105%, and the purity can reach more than 99%; in addition, the present invention adopts nitromethane as the solvent of reaction and also has the following advantages: weak smell , less pollution, less harm to the human body, easy post-processing of the product, improved purity, and no genotoxic impurity nitrobenzene residue in the final product.