Abstract Immobilized N-alkylaminopyridinium salts on divinylbenzene cross-linked polystyrene gel was reusable at least 8 times on the reaction of 4-chloronitrobenzene with anhydrous potassium fluoride in tetrahydrothiophene 1, 1-dioxide to give 4- fluoronitrobenzene in high yield. The immobilized catalyst was also successfully used for a synthesis of several aryl fluorides in good yields.