Abstract:At present, there are more than 100 sea-crossing channels built, under construction and proposed in the world and on all five continents. Developed countries in particular are at the forefront. The 19th National Congress of the Communist Party of China has made a strategic decision to build a strong transportation country. A large number of undersea tunnel super projects will also appear in China. Aiming at its characteristics, the construction limits of super-long undersea highway tunnel are analyzed and studied.