In order to improve corrosion resistance of galvanized steel, a novel cerium-phytic acid passivation treatment was studied. The process of cerium-phytic acid passivation on galvanized steel was optimized. The corrosion resistance of cerium-phytic passivated samples was tested by dropping test and weight loss test. The electrochemical behaviors of cerium, phytic acid and cerium-phytic acid passivated samples in 0.5 mol/L NaCl solution were investigated by polarization curve and AC impendence spectroscopy, respectively. The corrosion equivalent circuit established according to impedance characteristics. The corrosion current density of the samples were treated by cerium and phytic acid was 8.52 × 10-5 A/cm2 and 9.39 × 10-5 A/cm2, respectively, However, the samples were passivated by cerium-phytic acid the corrosion current density decreased to 1.76 × 10-5 A/cm2, respectively. The test results showed that cerium-phytic acid passivated samples exhibited better corrosion resistance than that of cerium or phytic acid passivated sample under the same test conditions.