Abstract: In an acidic sulfate system, a Sn/ZrO₂ composite coating was prepared by ultrasonic auxiliary electrodeposition to explore the effect of ultrasonic power, nanoparticle concentration and cathode current density on the corrosion resistance of the Sn/ZrO₂ composite coating. The influence of nanoparticles on the electrochemical reaction process in the Sn/ZrO₂ system was studied by linear sweep voltammetry and AC impedance spectroscopy. The coating morphology and microstructure were tested by SEM and XRD, respectively. The experimental results show that the best electrodeposition process is as follows: ultrasonic power of 300 W, nanoparticle concentration of 7 g/L, cathode current density of 2.5 A/dm². Under the optimal conditions, the electrodeposition process of the pure Sn coating and Sn/ZrO₂ composite plating electrodeposition was explored. The addition of ultrasonic auxiliary nanoparticles makes the coating surface denser, increases the active site of the deposition process, promotes the deposition of Sn²⁺ plus, refines the grain, and makes the coating surface flatter and denser.