Perfluorooctanoic　acid　doped　polyaniline　(PFOA/PANI)　nanoparticles　were　successfully　prepared　through　ultrasonication-assisted　oxidation　polymerization.　The　prepared　PFOA/PANI　nanoparticles　exhibited　high　hydrophobicity　and　good　dispersibility　in　ethanol,　which　could　uniformly　distribute　in　epoxy　resin　(EP)　coatings　to　enhance　their　anti-penetrant　efficiency　towards　corrosive　media.　The　corrosion　protection　properties　of　PANI-contained　coatings　on　Q215　steel　were　evaluated　and　compared　through　electrochemical　impedance　spectroscopy　measurements　in　brine.　The　experimental　results　demonstrated　the　PFOA/PANI/EP　coatings　possessed　higher　corrosion　performance　than　the　EP　coatings　and　HCl-doped　PANI-contained　EP　coatings.　Besides,　dedoped　PFOA　molecules　from　PFOA/PANI　nanoparticles　can　be　adsorbed　on　the　surface　of　steel　to　form　a　hydrophobic　corrosion　inhibition　layer,　which　further　improves　the　corrosion　resistance.　The　impedance　of　PFOA/PANI/EP　coatings　continuously　increased　after　the　coatings　were　immersed　in　brine　for　more　than　2　days,　and　the　impedance　modulus　at　0.01　Hz　was　higher　than　6　×　108　Ω·cm2　after　9　days.　The　novel　method　for　the　preparation　of　hydrophobic　PANI　nanoparticles　proposed　in　this　work　may　provide　new　ideas　and　methods　for　developing　more　high-performance　anti-corrosion　materials　and　promoting　their　applications　in　corrosion　protection.　©　2021　Elsevier　B.V.