Abstract: In order to get a further understanding the principle of electromagnetic interaction and study the regular phenomenon of arc interruption during the double-wire GMAW welding process, a series of experiments of different current matching are designed, then taking a picture of arc shape and collecting current and voltage waveforms simultaneously during the welding process. Analyses for the above-mentioned experiment results with displacement formula derived through the theory of electromagnetic then gets the same conclusion:the increase of another arc with the arc current ratio will increase the frequency of interruption of the arc. Finally, combining the captured images of the arc with the acquisition of current, voltage waveforms and analyzing the arc interruption phenomenon, the results show that the arc interruption phenomenon can be avoided by reasonable matching of welding parameters.