The invention provides an electroplating method of carrying out La-TiO2-Ag layer cyanide-free composite electroplating on the surface of a steel base material. The electroplating method is safe and environment-friendly, a preparation technology is simple, a La-TiO2-Ag layer is flat and smooth in surface, a coating is compact, is uniform in structural components and good in surface quality and presents metallic luster, the effect of the coating using a hydantoin series electroplating solution is far higher than that of a coating using a similar cyanide-free electroplating solution system, the stability of the electroplating solution is high, the corrosion resistance and the oxidation resistance are high, and the La-TiO2-Ag layer has better antibacterial and bactericidal performance.