Abstract: Since the multi parameters impacting on the weld geometry in triple-electrode high speed CO₂ welding, all the parameters can not be considered at one time, therefore the main parameters should be studied during the welding process. In this paper, two kinds of factors such as the middle electrode offset and the trailing electrode offset of three levels were studied to predict the weld geometry parameters using statistical method.The results show that the horizontal leg length and vertical leg length were effected by the main effect factors and the convexity degree was effected by the both effect of the main effect and interact effect.The predicted values of horizontal leg length is 4 mm, the vertical leg length is 2.5 mm and the convexity degree is 1 mm.