The work aims at studying the corrosion inhibition of zinc phytate on Q235 in NaCl solution and the protective performance of the composite epoxy coating. Zinc phytate nanoparticles were prepared from sodium phytate and zinc acetate. Their structure and morphology were characterized by infrared spectroscopy (IR), scanning electron microscopy (SEM), electron energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The corrosion behavior of Q235 in the solution containing zinc phytate extract was studied by open circuit potential and polarization curves. The surface corrosion morphology and composition after immersion were characterized by SEM and X-ray photoelectron spectroscopy (XPS). The dispersion state of zinc phytate nanoparticles in the epoxy coating and their effect on corrosion resistance were studied by SEM, electrochemical impedance spectroscopy (EIS), and neutral salt spray test. SEM and TEM showed that the synthesized zinc phytate nanoparticles were spherical particles with a uniform diameter of about 20-40 nm. The open circuit potential and polarization curves showed that the extract of zinc phytate nanoparticles could inhibit the corrosion of Q235 in 1wt.% NaCl solution. XPS showed that the Q235 sample adsorbed phytate and formed a film; SEM could observe that zinc phytate nanoparticles were well dispersed in epoxy resin without obvious agglomeration. EIS and salt spray tests showed that zinc phytate nanoparticles could enhance the protective performance of the epoxy coating. It can be concluded that zinc phytate nanoparticles can be used as an antirust pigment. Compared with zinc phosphate antirust pigment, the coating with the same amount of nano zinc phytate has a better anti-corrosion effect, which may be related to the small size, good dispersion, and excellent corrosion inhibition effect of zinc phytate.