The present invention relates to a plating method of a circuit substrate, a production method of a plated circuit substrate and a silver etching liquid. The plating method of the circuit substrate comprising a conductive pattern in which a metal layer containing at least silver and copper is exposed on an outer surface can suppress plating precipitation of the part outside of the conductive pattern and can form a good plating layer on a surface of the conductive pattern. The plating method comprises: step (A) of treating the circuit substrate with a first liquid agent containing an oxidizing agent; step (B) of treating the circuit substrate after the step (A) with a second liquid agent which dissolves copper oxide, and thereby removing copper oxide from the conductive pattern's surface; step (C) of treating the circuit substrate after the step (B) with a third liquid agent whose rate of dissolving silver oxide (I) at 25 DEG C is 1000 times or more faster than its rate of dissolving copper (0) at 25 DEG C, and thereby removing silver oxide from the conductive pattern's surface; and step (D) of performing electroless plating on the conductive pattern of the circuit substrate after the step (C).