The invention provides an automatic tube butt joint all-position TIG welding technology for coiled tubing. The technology comprises the steps that the tube ends at the two sides of the coiled tubing are straightened, the tube ends of the two sides are subjected to V-shaped edge preparation or U-shaped edge preparation, the inner wall and the outer wall of a joint between the tube ends are cleaned, then the tube ends are assembled in a butt joint mode, a butt joint of the coiled tubing is subjected to non-wire-filling backing weld, filling weld and cosmetic weld through the automatic all-position TIG welding technology, when the butt joint is welded, the arc starting position of a welding gun is located at 1:30 or 2:00, and a separated section welding technology method is adopted for welding. By means of the welding technology, aiming at the tube butt joint welding of the coiled tubing, the traditional manual TIG welding is transferred into full-automatic TIG welding, the working efficiency is improved, the labor intensity is lowered, and the welding joint of the coiled tubing of great comprehensive performances is obtained.