Abstract: In order to ensure the reliability and safety of offshore wind jacket fabrication,the study of the fracture behavior of welded joints becomes crucial.This paper introduces the fracture toughness assessment of welded joints from the concept of CTOD and the CTOD test method,and provides a new design and evaluation method for the offshore wind industry to improve the performance and sustainable development of offshore wind power jackets;At the same time,compare its economy and efficiency,and provide data support for promoting applications.