Abstract: In view of the sophisticated welding parameters of digital welding machine, large-scale technology experiments are difficult to be conducted. A unified pulsed MIG welding parameters adjusting technology based on least squares method has been proposed in this paper. The optimized fitting curve is achieved and the full advantage of the ideal data that generated in the experiments is utilized by applying a fitting relationship, which obtained through technology experiment, between the large-step welding current and other welding parameters. Besides, easier software program with simple algorithm is realized as well as a wide range of continuous adjustment of the welding parameters. Experiments are conducted after the fitting of singlepulse, double-pulse welding parameters. The experiments results indicate that the welding process is stable to obtain clear fishscale welding seam with uniformed appearance and fewer spatters. Thus, good stability, reliability and feasibility of the proposed method are well approved.