Graphene oxide-terminated partially fluorinated poly(arylene ether sulfone) (GO-PAES) was synthesized via step growth polymerization with graphene oxide. A small amount of graphene oxide was incorporated into the polymer matrix to enhance the properties of the polymer/GO composites. The chemical structures of the synthesized copolymers containing graphene oxide were confirmed by H-1 NMR and FT-IR spectra. The thermal properties of GO-PAES analyzed by TGA and DSC were significantly improved due to the thermal stability of graphene oxide.