We developed a facile approach to hyperbranched polymers by applying a superelectrophilic reaction within an A(2) + B-3 strategy. A significant reactivity difference between the intermediate and the starting material was utilized to avoid gelation in the A(2) + B-3 polymerization. A number of hyperbranched poly(arylene oxindole)s were achieved in a one-step polymerization and characterized by NMR spectroscopy and gel permeation chromatography. Moreover, further modifications at the interior and exterior of the resulting polymers were explored as well.