The surface of Al flake powder was modified with aluminum zirconium organic metal coupling agent. The resulting flakes were incorporated into epoxy coatings as anticorrosive pigments. The energy dispersive x-ray (EDS) tests and scanning electron microscopy (SEM) tests indicated that the coupling agent improved the dispersion of Al flake powder, so that the flatness, adherent and shielding effect of the coatings was greatly enhanced. The electrochemical impedance spectroscopy (EIS) results of coatings in 3.5% NaCl solution showed that, in the initial immersion stage the coatings exhibited larger impedance values and better corrosion resistance after modification. In addition, after 52 days of immersion, the coatings before modification had no corrosion resistance, the coatings after modification still displayed good corrosion protection with an impedance value of 106 Ω cm2, and the epoxy coatings exhibited the highest protective performance when 2.5% of the coupling agent was used.