Alkaline semi-bright non-cyanide immersion chemical silvering solution and preparation method thereof

The invention discloses an alkaline semi-bright non-cyanide immersion chemical silvering solution and a preparation method thereof. The silvering solution is stable and can be preserved for more than three years at the room temperature, the efficiency is high, the bonding force of a plating layer is good, and the surface of the plating layer is flat, semi-bright and good in anti-tarnish property. The silvering solution is easy to maintain, and only silver ions need to be supplemented during long-term operation; and in addition, the silvering solution is high in anti-pollution capacity and copper ion tolerance.