The composition of MK7 jet blast deflector mechanical system was introduced and the motion diagram of the mechanism was given.The simulation model of the jet blast deflector mechanical system was established by using AMESim software under certain assumptions.The motion and dynamic performance of the jet blast deflector mechanical system was simulated and analyzed under certain input.The result shows that the MK7 jet blast deflector has good motion and dynamic performance,but there is still room for improvement in its load-bearing performance when subjected to the jet action of shipborne aircraft’s tail flame.The results provide reference for innovative design of jet blast deflector.