Abstract: In order to meet the welding task of duplex stainless steel pipe used for the production water treatment process in an overseas oilfield,reasonable welding materials,welding methods,optimized welding procedure and precautions during welding were proposed for welding difficulties and particularities of S31803 duplex stainless steel through analysis of material’s weldability and repeated tests. Physical and chemical properties tests of welded joints were also carried out. The results showed that the welded joints were satisfied with both welding standards and design requirements.