•GO-PANIs/Epoxy nanocomposites were fabricated and analyzed.•GO-PANI composites improved the corrosion resistance of the epoxy coating.•GO-PANI I significantly improved the barrier/active performance of epoxy coating. Graphene oxide nanosheets were functionalized with polyaniline (PANI) nanofibers through three methods In method II the polymerization of aniline was done in the presence of sodium dodecyl sulfate as a surfactant and ammonium persulfate as an initiator. In method I the surfactant and in method III the initiator were eliminated during polymerization procedure. The morphology and chemistry of the nanosheets were characterized. Then, the GO/epoxy and GO-PANIs/epoxy nanocomposites were fabricated and their corrosion protection performance was studied on steel substrate by electrochemical impedance spectroscopy. Results revealed that GO-PANI remarkably improved the barrier performance and provided active inhibition for epoxy coating.