The high surface roughness of selective laser melting GH4169 alloy is a challenge that need to be resolved in its application. To replace the traditional acid based electrolyte, choline chloride-ethylene glycol system (Deep eutectic solvent, DES) was used for electrochemical polish GH4169 alloy fabricated by selective laser melting. In order to explore the ethanol addition effect on the electrochemical polishing behavior of the alloy, surface morphology, roughness, glossiness, wetting angle and electrochemical properties before and after electrochemical polishing have been investigated. The result indicates that the surface quality of the specimens after electrochemical polishing has been significantly improved. Among them, when the molar ratio of choline chloride∶ethylene glycol∶ethanol is of 1∶1.9∶0.1, and the processing parameters are of temperature 60 ℃, time 30 min, voltage 3 V, magneton rotation speed 240 r/min and electrode spacing 13 mm, the surface of the specimen shows much more smooth and bright, and the roughness R_a is (0.403 ± 0.010) μm, and the glossiness is (357.9 ± 2.2) GU. The wetting angle and electrochemical properties have also verified that the surface of the sample after electrochemical polishing is more beneficial to corrosion resistance. Meanwhile, the mechanism of the alloy electrochemical polishing in choline chloride-ethylene glycol system has also been discussed.