Abstract: Effects of argon tungsten arc welding technology and parameters on formation of weld and bearing capacity of thin-walled ring titanium alloy were investigated through experiment, and effects of vacuum stress relieving annealing and vacuum annealing on weld formability were compared and analyzed. The results indicated that welds obtained by automatic argon tungsten arc welding, pulse peak current 55 A, base current 27.5 A, welding speed 120 mm/min, and argon flow 10 L/min on front and back, without adding welding wire met the requirements. Compared with vacuum stress relieving annealing after welding, hardness of welds after vacuum annealing was significantly reduced, and plasticity of welds was improved, which was more conducive to plastic forming, and solved problems of high hardness and poor plasticity of weld and easy crack during forming. When weld and tension direction was 45°, it was conducive to welding of welds and improvement of bearing capacity of welds, which was increased to 1.4 times of the original.