A mild method for palladium-catalyzed halogenation of acetanilide with N-chloro-N-fluorobenzenesulfonylamide (CFBSA) as a chlorinating reagent, oxidant, and novel promoting reagent was achieved. The decomposition of byproduct N-fluoroben-zenesulfonylamine in the presence of Pd(OAc) 2 could accelerate the process of chlorination. Preliminary mechanism investigation showed that Pd catalyzed anilide directed C-H activation lead to the ortho chlorination selectivity. A series of ortho-chlorinated anilides were obtained in 28%～82% yields.