Sulfuric acid solution was used to be the polishing slurry for the electropolishing of Ni5W alloy substrates prepared by rolling-assisted biaxially textured technology. The substrates with different surface states were obtained in several polishing slurry concentrations. The phase compositions of the surface mass and the microstructures were investigated by XPS, XRD, AFM and SEM, respectively. The results show that the low concentration polishing slurry promotes the excess production of oxides and H2WO4 which can disorder the process of selective solution disorder. The best effect can be obtained in 8.76 mol/L polishing slurry which promotes the formation of solid layer and mucus layer in proper thickness.