Display omitted •The NC dispersion in epoxy matrix was enhanced by graphene oxide nanosheets.•The G/N:34/66 loaded coating showed the highest corrosion protection degree.•The G/N:34/66 loaded coating resulted in the lowest coating cathodic delamination. In this study, Graphene oxide (GO) nanosheets were studied to improve nanoclay (NC) exfoliation in a phenol novolac glycidyl ether and improve coating performance. Particle characterizations are performed by FT-IR, Raman spectroscopy, and FE-SEM methods. EIS measurements confirmed denotative stability in impedance values, more significant than 1010 ohm·cm2, after prolonged immersion time (18 weeks). Complementary characterizations, salt spray test, pull-off, and cathodic disbondment test, revealed that such enhancement in the clay dispersion has significantly improved the coatings protection function.