Abstract: The latest 8th Edition of API Spec 5CT contains some significant changes and amendments to the previous edition, among which the biggest one is that for the first time three classes are specified for tubing and casing products. The main differences between the 8th edition and the 7th edition of API Spec 5CT are identified and compared, and the influence by the said latest standard on domestic oil tubing and casing processing industry is analyzed on the basis of the general technological requirements for tubing and casing processing that is an additional part of the new edition, and the technological and equipment level of domestic OCTG processing industry.