The product is a compound polymer complex, which can generate stable metal complex ions with various metal ions under alkaline conditions, so as to achieve the formation of single metal or alloy coating. The reagent is a common chemical, low toxic, phosphorus free, and an environmental protection electroplating raw material. It can replace highly toxic sodium cyanide and is widely used in various cyanide replacement electroplating processes, such as alkali copper, bronze, cupronickel tin, brass tin, gold plating, silver plating and etc.