With the ever-increasing functional requirements of wharves,many existing wharfs can no longer meet the berthing demands of large vessels and are in urgent need of renovation and upgrading.Aiming at a series of problems in the renovation and upgrading of existing wharves,such as limited construction sites from simultaneous operation and renovation,tide-dependent construction caused by water level fluctuations,and the 100-year durability requirement for the structure,this paper introduces the application of a new precast breast wall in the renovation and upgrading of existing wharves.By comparing the combined precast and cast-in-place breast wall scheme with the traditional full cast-in-place breast wall scheme,carrying out theoretical calculation and analysis,and citing practical engineering project examples,this paper concludes that the combined precast and cast-in-place breast wall scheme can effectively solve construction difficulties caused by limited construction site space,water level variation,structural durability and other factors.Meanwhile,it eliminates the time consumed by working procedures such as formwork erection and removal on the seaward side during concrete pouring as well as concrete hardening,thereby shortening the construction period.The research results can provide a practical basis for subsequent similar reconstruction and renovation projects of existing wharves,and promote innovation and development in the field of wharf upgrading and reconstruction.