The drainage immersed pipe method is widely used in the drainage engineering of costal power plants at present.With the continuous construction of new projects,the new design methods and key technologies of drainage immersed pipe are constantly developed and improved.Based on the existing and under construction drainage immersed pipe projects at home and abroad,this paper studies the foundation treatment method,joint treatment method,floating transportation and installation technology and other related technical problems in the construction process of drainage immersed pipe.This paper summarized drainage immersed pipe stress conditions in the process of installation,use and maintenance.A systematic method for structural calculation of drainage immersed pipe is put forward.The finite element software ANSYS is applied in numerical calculation.The structural analysis of the whole life cycle of immersed pipe is realized.The key technology and calculation method of drainage immersed pipe in power plant drainage are studied,which can provide reference for similar projects.