<p>Titanium alloys are widely used in the marine environment due to their excellent corrosion resistance and comprehensive mechanical properties. However, when titanium alloys connect with different metals such as carbon steel, galvanic corrosion is likely to occur. In order to reduce the galvanic corrosion between titanium alloys and other metals, TC4(MAO)/CrN film was produced on the surface of the titanium alloy by micro-arc oxidation/multi-arc ion plating. The microstructure and galvanic corrosion behavior were analyzed. The results show that the micro-arc oxidized film layer of titanium alloy had a crater-like porous structure with the porosity of 7.6%. CrN ceramic layer was plated on the surface of the micro-arc oxidized film layer to seal the pores, reducing the surface porosity to as low as 2.7%. The physical phase composition of the CrN film layer primarily consisted of CrN, Cr, and trace amounts of Cr₂N; after the composite treatment, the self-corrosion potential of the titanium alloy surface shifted positively from − 0.16 to 0.0143&#xa0;V. The average galvanic current density decreased from 3.5 to 0.34&#xa0;μA/cm², a reduction of 90.3%, and galvanic corrosion grade improved from E to B. The average galvanic corrosion rate decreased from 1.69 × 10⁻⁴ to 3.3 × 10⁻⁵&#xa0;g&#xa0;m⁻²&#xa0;h⁻¹. The tensile strength and elongation increased by 9.5 and 23.5%, respectively.</p>