The GB/T 27581-2011 standard specifies the determination method of nickel ion and copper ion content in electroless copper plating solution for electromagnetic Shielding film. The standard applies to electroless copper plating solution with nickel Ion concentration ranging from 0.20 g/L to 2.00 g/L and copper Ion concentration ranging from 5.0 g/L to 60.0 g/L. In the method, copper ions are masked by EDTA, and nickel ions are converted into burgundy complexes using ammonium persulfate as an oxidation agent. The nickel content is determined by photometry. Meanwhile, the determination of copper ions adopts the potential Titrimetric method. Titration is performed using a copper Ion selective electrode. The concentration of copper ions is determined by calculating the consumed EDTA standard volume solution.