Abstract: This paper discusses the high frequency pulsed current helium gas tungsten arc welding of LD10 high-strength aluminum alloy.The reasons for its adoption,the laboratory type high-output transistor power source,the welding process,as well as its advantages are described.Experiments indicate that by using this process to weld LD10 high-strength aluminum of 5mm thickness with square groove,a weld joint can be done by one side single pass welding.The single-pass weld has excellent internal quality and good surface appearance on both sides.Because of the high frequency and strong penetration characteristics,the process gives a greater depth-to-width ratio,a smaller transverse section of weld,a finer microstructure and better weld joint in quality than AC argon arc welding and DC helium arc welding.