Abstract: Phytic acid and silane modified graphene oxide (PSGO) nanomaterials were added into a high solid content polyaspartic acid ester (PAE) coating system to prepare environmentally friendly high solid content PSGO/PAE composite coatings. Salt-spray corrosion test, electrochemical test and field application test were carried out to study the anti-corrosion performance of the PSGO/PAE composite coating, and the anti-corrosion mechanism of the coating was preliminarily investigated. The results show that the addition of PSGO could significantly improve the corrosion resistance of the PAE coating. After soaking for 28 days, the |Z|_{0.01 Hz} of the composite coating still reached 1.35× 10¹⁰ Ω·cm². The PSGO/PAE composite coating with 0.5% (mass fraction) PSGO had excellent anti-corrosion performance in the atmospheric environment of the South China Sea. The synergistic effect of phytic acid's passivation protection on metal materials and graphene oxide nanosheets' barrier shielding enable the PSGO/PAE composite coating to provide dual protection for metal substrates. And the coating is expected to be applied to marine heavy anti-corrosion and other fields.