The invention relates to a method for preparing a hydroxyapatite and
bone collagen composite coating on the surface of a
magnesium alloy. The method comprises the following steps: preparing a deposition solution, wherein in the deposition solution, the concentration of
calcium nitrate is 0.02-0.05 mol / L, the concentration of
sodium phosphate is 0.002-0.005 mol / L, the concentration of
bone collagen is 0.5-2.0 g / L, and the pH value of the deposition solution is 3.0-4.0; carrying out ultrasonic cleaning on the
magnesium alloy for 8-10 min in
alcohol and
acetone after
polishing treatment, and then putting the
magnesium alloy in the deposition solution for deposition for 6-24 h, wherein
ultrasonic oscillation with the power of 100-150 W and the frequency of 30-45 KHz is adopted in the initial stage of deposition for 5-15 min. The preparation method is simple, the prepared and obtained hydroxyapatite and
bone collagen composite coating is low in degradation velocity, the biomedical
magnesium alloy with the
coating is higher in
corrosion resistance, and the bone collagen is added into the deposition solution, so that the
nucleation and growth of the hydroxyapatite can be quickened, and the
corrosion resistance of materials is improved.