A novel Pd-catalyzed intermolecular regio- and diastereoselective fluorosulfonylation of styrenes has been developed under mild conditions. This reaction exhibits a wide range of functional-group tolerance in styrenes and arylsulfinic acids to afford various beta-fluoro sulfones. Preliminary mechanistic study reveals an unusual mechanism, in which a high-valent (L2PdF)-F-III species side-selectively reacts with a benzylic carbon radical to deliver a C-F bond. This pathway is distinct from a previously reported radical fluorination reaction.