Abstract: Tandem dual-wire welding technology is one of the effective welding methods to improve welding efficiency. Aiming at the current problems of low pipeline welding efficiency, poor fusion of sidewall and base material during welding, and unstable weld molding quality, the process method of Tandem dual-wire co-melt pool narrow bevel welding was proposed. X65 steel as the test base material, based on Minitab's Taguchi method to carry out the entire welding test, the influence of the combination of wire feeding speed, welding speed and arc length correction of the process parameters on the weld forming law were explored. The results show that, a well-formed weld can be obtained when the wire feeding speed is v_f=4.4 m/min, the welding speed is v_w=26 cm/min and the arc length correction is η=8%. This study also lays the foundation for the subsequent all-position welding of narrow beveled pipes with Tandem dual-wire co-melt pool.