Abstract: The ultra-supercritical high temperature and high-pressure working conditions can easily lead to the initiation of cracks in the welded joints on the main steam pipelines of thermal power plant units during service, causing early failure and seriously affecting the safety and stability of unit construction and operation. The overviews of the influencing factors,creep behavior characteristics and the development and application of crack failure assessment rules for pipeline welding joints in ultra-supercritical thermal power units were summarized. The future research focus and direction in this field were also looked forward, which can provide theoretical reference and research basis for preventing early failure of high-temperature thermal pipeline welding joints and evaluate structural integrity in power plants.