The suffite gold electroplating process on silicon wafer is described in the paper. The maintenance of electroplating and affecting factors of constant current electroplating gold are also described. The suffite gold plating process is optimized and the process parameters are determined. The most optimal parameters：Gold is 10 g/L，sodium sulfite is 140 g/L，potassium dihydrogen phosphate is 40 g/L，potassium citrate is 80 g/L，potassium chloride is 100 g/L，EDTA-2Na is 10 g/L，sodium dodecyl sulfate is 0.01~0.2 g/L，brightener is 20 g/L，pH is 7.5~8.0，cathode current density is 2.1 mA/ cm2，anode is platinum mesh，magnetic strirring speed is 200 RPM，and the temperature of electroplating solution is 45 ℃. The obtained films are brightly golden yellow. The morphology and composition of the electroplating gold film under the optimal conditions are analyzed by the SEM and EDS techniques. The results show that the micro-morphology of the gold film is smooth and dense，and the purity of the gold film is very high. The research objective is to solve the problem of electroplating gold on surface electrode，which requires stable performance of electric parameters on laser wafer in the long term.