Abstract: With high alloy content above 80%,the nickel base alloy tubing/casing are regarded as important products related to the national energy safety,and mainly used for exploitation and exploration of extra-large marine natural gas fields with complex geological structure,hi-temperature and hi-pressure,and hi-corrosiveness. Such pipes are also honored as the most hi-technologically-valuable ones among the OCTG products due to their critical service conditions,complex manufacture processes,high difficult degree for production,and stringent product quality requirements. Summarized in the paper are the technological characteristics and quality requirements of the nickel base alloy tubing/casing;described are quality and properties of such products as made by Baoshan Iron and Steel Co.,Ltd.,and moreover analyzed by such micro-analysis methods as XPS and TEM,etc are the anti-corrosion behaviors and mechanism of the said pipes relating to their high resistance against H₂S,CO₂,Cl^- and the single substance S.