Abstract: As the weak link of natural gas transmission pipeline, the welded joints of pipeline are more prone to corrosion failure in the highly corrosive coastal soil environment. The corrosion factors and main corrosion types of welded joints of natural gas pipelines in coastal towns in China are reviewed, and the main pipeline protection technologies are introduced, including adding corrosion inhibitor, anti-corrosion coating, improving corrosion environment and cathodic protection. Finally, combined with the increasing demand for comprehensive utilization of hydrogen energy, the risk of hydrogen embrittlement in welded joints of hydrogen mixed natural gas pipelines is analyzed, and the key technologies for developing hydrogen resistant coatings to ensure the long-term safe service of hydrogen mixed natural gas pipelines in the future are prospected.