A new TiO2-modified film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural net was used to optimize the preparing condition of the film. The optimized condition of the TiO2-modified film on carbon steel is as follows: plating time of NiP is 50 min, number of dip coating is 4,heat treatment time is 2 h, and the molar ratio of complexing reagent to Ti(OC4 H9 )4 is 1.5: 1. Corrosion behavior of carbon steel with coating was investigated by polarization resistance measurement, anode polarization, EIS and ESEM measurement. XPS was used to characterize the element valence of the modified film. Results show that carbon steel with TiO2-modified film has good corrosion resistance in 0.5 mol/L of H2 SO4 solution and 0.5 mol/L of NaCl solution. It is also found that the preparing condition of forming TiO2-modified film can be obtained easily by the artificial neural net.