The core component of offshore floating mooring and crude oil transportation equipment is the crude oil transportation system, in which the strength of the pipelines at the buoy and 100 m underwater is the main factor to ensure its service life. A dedicated stress analysis software is used to analyze the stress of the crude oil transportation system pipeline at the buoy. Combining the limitations of the buoy structure on pipeline layout, an optimized layout plan is proposed to ensure pipeline strength; for the pipeline at the underwater manifold, by analyzing the load on the underwater manifold and considering the particularity of pipeline layout, a combination of theoretical strength verification formula and stress calculation using software is adopted for the analysis. Based on the theoretical formula, the pipeline thickness is selected, and the pipeline stress analysis method is used to verify the pipeline strength. At the same time, guidance is given to the underwater pipeline layout and optimization of pipe support settings.