The preparation technology of micro-nano structure on copper surface is studied and optimized. Aqueous solution containing sodium carbonate and sodium molybdate is used as electrolyte, and the copper sample is anodized at a constant voltage to form a layer of oxidation on the copper surface. Then, the copper surface is treated with aqueous solution containing phosphate and sodium dihydrogen phosphate as corrosion solution to obtain a micro-nano structure on the copper. The surface is observed by using a scanning electron microscope. Finally, the analysis software is used to analyze the scanning electron microscope image to calculate the micro-nano structure pores on the copper surface. The results show that when the anodizing voltage is 15 V, the anodizing time is 20 min, the phosphoric acid mass fraction is 20%, and the corrosion time is 30 min, the copper surface is relatively smooth, and the porosity reaches 25.77%. Orthogonal experiments demonstrate that the type, concentration of the corrosive solution, and etching time have a great effect, while the anodizing electrolyte, voltage and electrolysis have no significant effect on the porosity. Using a combination of anodic oxidation and chemical corrosion, micro and nano junctions with uniform and high porosity can be prepared on the copper surface.