In this study, the surfaces of high-strength AZ61 and AZ91 were treated with a multifunction cavitation treatment (MC-MFC) containing phosphoric acid to improve corrosion resistance and fatigue properties. The treated surfaces were evaluated using SEM, FT-IR, and contact angle. A golden-colored film was formed on the sample surface after MC-MFC treatment. However, the surface roughness increased after treatment. This increase in surface roughness was suggested to be due to the involvement of network-like compounds formed after treatment.