Undersea tunnel is a relative new thing in the engineering field in China. At present, Chinese builders lack construction technologies and construction experience in undersea tunnels, especially the safe and rapid construction technologies in tunneling through fault and fracture zones. For the construction of Qingdao Jiaozhou Bay undersea tunnel, the builders  atsorbed the advanced construction technologies both at home and abroad and depend on themselves. So far, they have conquered a series of technical problems, especially the construction difficulties in tunneling through undersea fault and fracture zones. The construction of Qingdao Jiaozhou Bay undersea tunnel not only accumulates many practical and comprehensive construction experience, but also can provide reference for similar projects in the future.