In order to find a green and efficient passivation method to improve thecorrosion resistance of galvanized steel，silanized cerium salt/tannic acid passivation combined with resin sealing sample was prepared，and the corrosion resistance and corrosion mechanism of the sample were studied. The surface of hot-dip galvanized steel was first passivated bysilanized cerium salt/tannic acid，and then sealed by epoxy resin and amino resin. The corrosion resistance of the materials was tested by electrochemical test and neutral salt spraytest. The composition and microscopic morphology of the material were studied by SEM-EDS.The electrochemical test results showed that the corrosion resistance of the samples passivatedby silanized cerium salt/tannic acid and sealed by epoxy resin was the best，with the impedance modulus at 10^-2 Hz exceeding 10^{7. 5} Ω ·cm²，a polarization resistance of 345 303 Ω ·cm²，and a corrosion prevention efficiency of 99. 98%. After 48 hours of neutral salt spray test，the surface of the sample showed almost no corrosion；and the SEM-EDS results indicated that there were very few surface defects in the sample. Under experimental conditions in the article，the corrosion resistance performance of samples sealed by epoxy resin was better than that ofsamples sealed by epoxy resin+amino resin. The presence of cerium salt and tannic acid couldgenerate cerium oxide and other components to prevent further corrosion of the materials，and enhanced the bonding between the resin and galvanized steel plate，improving the corrosionresistance of the materials. The anticorrosion mechanism of this passivation method mainlycombines the shielding effect of binding resin，the film forming performance of cerium ion and the combination of tannic acid and cation，which is an excellent passivation method that meetsthe requirements of environmental protection.