In order to improve the corrosion resistance and biological activity of pure magnesium, chlorogenic acid extracted from traditional Chinese medicine was deposited on ultrasonic micro-arc oxidation surface by electrophoretic deposition. The surface morphology and organizational structure of various samples were studied by scanning electron microscopy, X-ray diffractometer, atomic force microscopy, X-ray photoelectron spectroscopy, fourier transform infrared spectroscopy and contact angle measuring instrument. The corrosion behavior and resistance of various samples were also studied and evaluated. The main phase composition of UMAO/CS/CA coating is Mg, MgO and Mg2SiO4, and the main elemental compositions are O, C, Mg, Si and N. The stretching vibration peaks of O—H, aromatic hydrocarbon bonds, C==O bonds and benzene rings appear in CA coating. Chinese herbal extract and chitosan are mainly combined by chemical binding and physical adsorption. The UMAO/CS/CA coating is a hydrophobic surface, the contact angle of that is 104.1°. Electrochemical corrosion experiments show that the corrosion current density (Jcorr) of Mg is 1.7569×10?5 A/cm2 in simulated body fluid (SBF) environment. Among them, the icorr of UMAO/CS/CA coating is 3.767×10?6 A/cm2, which reduced by at least one order of magnitude compared to that of Mg. UMAO/CS/CA coating can better induce calcium and phosphor deposition. The UMAO/CS/CA coating can not only reduce the contact area between the corrosion solution and the coating surface, but also isolate the ions in the solution, which is difficult to be wetted by SBF, and can provide more effective protection for the magnesium matrix. UMAO/CS/CA coating has excellent biological activity.