Using　an　environmentally　friendly　acid-alcohol　system　solution　for　electrochemical　polishing　of　3D　printed　titanium　alloy,　a　typical　U-I　polarization　curve　was　obtained,　and　explained　the　mechanism　of　electrochemical　polishing.　In　this　paper,　the　influence　of　electrochemical　polishing　factors　(electrolyte　temperature,　polishing　distance,　and　polishing　time)　on　the　surface　roughness　of　Ti-6Al-4V　(TC4)　was　studied,　and　optimized　the　process　parameters　to　obtain　a　surface　roughness　of　0.3　mu　m　(1　mm　x　1　mm).　Electrochemical　polishing　can　reach　the　level　of　mechanical　grinding　and　polishing,　meeting　the　requirements　for　subsequent　assembly　and　use.