Aiming at the problem of low qualified rate of high temperature alloy bracket welding,a Six Sigma project was launched. Through the five stages of definition,measurement,analysis,improvement and control,the welding process flow is analyzed,the potential factors affecting the weld quality are determined,and the key factors are determined through the two methods of double ratio test and chi square test. Finally,through the design test,the key process parameters are optimized and the optimal process parameters are determined. When the improved process plan is applied to the actual production,the welding qualification rate is increased from 35% to 95.8%,and the annual scrap and repair cost is saved by 627000 yuan. This paper proves the feasibility of Six Sigma method in the field of welding and provides reference value for the production and improvement of similar products.