Abstract: Described here in the article is a manufacturing process as properly getting the hot-rolling,the hot-expansion and the cold-rolling technologies integrated for producing the large-sized duplex stainless seamless steel tube. The low temperature impact toughness of the tube is significantly increased by means of the blooming forging process;and the precipitation of the harmful phases like σ,and development of surface cracking are avoided via properly controlling the heating scheme and the cooling rate during the hot-work and heat treatment processes. The S32205 large-sized,light-wall seamless steel tube is tested in terms of metallographic structure,ambient temperature mechanical property,instantaneous high temperature tensile property,and corrosion resistance. The test results are all satisfactory to applicable requirements.