The effect of welding current on the mechanical properties and microstructure of deposited metal of high-grade X80 high-efficiency gas shielded welding wire is studied,which provides a basis for automatic welding of pipeline engineering and welding process selection in alpine regions. The results show that under the welding current of 150～250 A,the deposited metal of X80 pipeline steel welding wire（1.0） has good strength and toughness;as the welding current increases,the impact toughness of the weld decreases. For every 10 A increase in welding current,the impact energy at -30 ℃ and -50 ℃ decrease 4 ～5 J,the microstructure of the weld is mainly composed of fine ferrite,which gives the material excellent toughness characteristics.