Abstract: The frame of a quantitative assessment method of aircraft guarantee systems on large aircraft carrier is presented.Combing the fuzzy theory and damage tree analysis,a fuzzy damage tree of the aircraft guarantee system is built.The numerical results of ship equipment by finite element codes are taken as a data system for vulnerability assessment,which makes the assessment more creditable.A simulation example of the system vulnerability analysis under JDAM attack is given for illustration.The results indicate that the presented assessment system is useful for ship systems vulnerability evaluation and survivability optimum design.