A three-step reaction furnished a composite of graphene and a conductive polymer. In the first step, graphene oxide was modified with a diamine, which acted as a linker for polymer attachment. In the second step, an initiating site was attached to the free amine of the linker. Finally, a polymer was grown from the initiation site, and graphene oxide was reduced during polymer growth. The method does not require any catalyst, acid, or reducing agent, furnishing the graphene-polymer composite in a straightforward procedure. Various instrumental techniques, including step-by-step AFM analysis, were used to characterize the structure of the products in each step and confirm the covalent functionalization among graphene oxide, cross-linker, and polymer. The average surface height was sequentially increased after each step, indicating the success of the sequential reactions. The graphene-polymer composite showed excellent electrochemical performance and stability compared with a composite prepared by physical mixing of graphene and polymer.