The types and the application of the pressure relief valves are introduced in detail according to the current situation that the calculation and selection of the pressure relief valves in the piping system of the floating production storage and offloading (FPSO) vessel depend on the valve manufacturer. The calculation and selection of the pressure relief valves in the piping system of the SBM FPSO vessel are carried out by using the API calculation method. The calculation method optimizes the overpressure mode and the selection of the valve flow area, ensuring the correct selection of the pressure relief valve and the safety of the piping system of FPSO vessel.