Abstract: The present paper describes the welding current characteristics of rotational arc MAG welding in V groove.It is found that the compulsively short circuiting transfer would take place when the welding gun rotates to the sides of V groove.The reason for this phenomenon is that the contact tip distance between the wire tip and workpiece becomes short when the welding gun moves to the sides of groove.During the period of short circuiting transfer,the welding currents would sharply increase,so as to affect the rotational arc sensor sensitivity.A hybrid filtering method based on spatial neighborhood mean filter and soft threshold wavelet filter is proposed to process the welding currents,and the real-time characteristics of this method is researched in this paper as well.The experimental results show that the hybrid filtering method has a higher filtering property and better real-time character.This study will set up the foundation for the welding gun deviation identification in the welding seam tracking.