The method of Failure Mode and Effect Analysis (FMEA) is used. Taken the fast de-ballast system as the research object, the ballast system, tank level measurement system, bilge system, Integrated Control and Monitoring System (IAS) and valve remote control system are deeply analyzed. The results show that the potential risk of the bilge system is the highest, which is the weakest link of the whole fast de-ballast system, and the tank level measurement system is the subsystem with higher reliability.