The invention discloses a preparation method for difluoromethyl-substituted sulfoaryl sulfonate. The preparation method comprises a step of subjecting a compound as show in a formula 2 which is described in the specification or a salt thereof and difluoromethanesulfonyl chloride to difluoromethylthiolation in an organic solvent so as to obtain a compound as show in a formula 3 which is described in the specification, wherein the organic solvent is one or more selected from a group consisting of a chloralkane organic solvent, a chlorinated aromatic hydrocarbon organic solvent, an aromatic hydrocarbon organic solvent and a nitrile organic solvent . The preparation method of the invention has the advantages of a wide scope of applicable substrates, mild reaction conditions, a high reaction conversion rate, high yield, high product purity and good industrial production prospects.