A new polystyrene-anchored palladium(II) catalyst has been prepared and characterized by conventional spectroscopic methods and elemental analyses The catalyst was found to be highly effective for the Suzuki cross-coupling reactions of aryl halides with arylboronic acid in water medium under phosphine-free reaction conditions The optimal reaction conditions of the coupling were determined The present heterogeneous Pd(II) catalyst was reusable as well as air-stable to allow easy use