A copper-silver dual-component metal electroplating solution includes copper methanesulfonate, silver methanesulfonate, methanesulfonic acid, chlorine ions, and water. An electroplating method for forming a copper-silver dual-component metal by using such an electroplating solution, the steps of which includes (a) contacting the copper-silver dual-component metal electroplating solution with a substrate; (b) applying an operating voltage, the current density of which is controlled to be between 0.1 and 2 ASD in order to carry out electroplating on the substrate. Therefore, the electroplating solution has environmental characteristics, such as less poisoning hazards, through the design of methanesulfonic acid and methanesulfonate electroplating solution. Also, the potential and the current are adjusted during the electroplating in order to obtain a copper-silver dual-component metal plating layer with a specific silver content.