Abstract: To solve the construction problems of immersed tube tunnels in special water environments (soft soil and high siltation), it takes the Yuzhu Tunnel project as an example. Through finite element modeling, the deformation characteristics of the retaining structure for onshore open-cut foundation pits were analyzed, and the stability of the foundation pit structure in the onshore tunnel section was verified. Further, key construction technologies were discussed, including immersed tube trench excavation, immersed tube segment installation, underwater joint construction of immersed tube segments, foundation construction, and backfilling and covering during the construction of immersed tube tunnels.