A titanium-salt conversion treatment processon hot-dip galvanized coating was studied. The effects of conversion solution composition and process parameters on the formation and corrosion resistance of the conversion coating on the surface of hot-dip galvanized coating were investigated. The morphology and composition of the coating were characterized. The stability of titanium-salt solution was analyzed. The optimal process parameters were determined as follows: TiOSO4 0.9g/L, C2H2O4 2.5g/L, phosphorus compound 3.0g/L, pH 1.3,25℃, 5min. The corrosion resistance of the hot-dip galvanized sample treated with the process was improved and salt spary test was up to 160 hours. Replacing H2O2 with C2H2O4 replacing could greatly improve the stability of the passivation solution.