Objective The effect of nanometer nickel technique modification on continuous industrial electro-galvanized line was analyzed, in order to further improve the surface quality of the zinc coating. Methods Simulated gravity high-speed electro-galva-nized equipment was applied in the nanometer nickel test on the surface of IF steel (interstitial-free steel), to discuss the repairing effect and mechanism of nanometer nickel for the scratch defects of the steel panel, and analyze the influence of nanometer nickel electroplating time on the morphology and texture of the zinc coatings. Results Nanometer nickel was preferentially deposited at the defect positions of the substrate, and had good filling effect on the scratches of the substrate. The nickel coating was well bonded with the substrate. With the increase of nanometer nickel electroplating time, the crystalline size of the zinc coating decreased, the crystalline state became dense and intensity of the (002) texture was significantly enhanced. Conclusion Embedding nanometer nickel in continuous electro-galvanizing line had benefit for repairing substrate defects and optimizing crystalline of zinc coatings.