In view of the strong dependence on welder’s operation skills in pipeline welding process,difficult control of welding specifications,and poor weld consistency,a welding electrode（welding gun） angle auto-aligning fixture for pipe welding is designed. The fixture can force clamping electrode（welding gun） to rotate synchronously along the weld of annular pipeline,which can realize precise control of welding electrode compared with the direction of the welding electrode,and the operation needs of transverse oscillating of welding electrode（welding gun）,with reasonable welding parameters selection,to assist the welder improve the quality of welding.