Gas welding was usually used for welding of T2 copper and 304 stainless steel before. Because the product is used in high temperature, the welded joint is easy to loose when heating,the leakage is caused and joint strength reduces,some joints can not meet the requirements. After repeated tests,it is found that the argon arc welding is better than gas welding for welds of T2 copper and stainless steel. Argon arc welding is easy to operate and its welding quality is stable. It also can reduce manufacturing cost greatly,shorten production period and enhance the strength of joints.