For swell dominated sea areas，no matured and detailed general layout design method for sea port engineering exists in domestic and foreign codes. Taking a specific sea port in Gulf of Guinea as an example，based on the owner’s requirement of the project’s downtime ratio shall be less than 1%，we investigate the 23 years hindcast time series data of concurrent wind，wave，tide，and current following the basic principles of layout arrangement in the international codes and guidelines，and optimize the general layout arrangement by the means of numerical wave model，ship maneuvering and mooring analysis，under keel clearance analysis for the main design vessels. The results show that the optimized layout scheme has the advantages of user friendly，short construction period and low cost，which can be used as a reference for the similar projects.