The coupling relationship analysis between the restrictive protection parameters of aero engines is the key to optimize the design of the control system and improve the safety and response quality. In order to solve the problem of analyzing the limit protection parameters coupling relationship only from safety margin, only the overall coupling change law of the limit protection parameters can be obtained, this paper proposes a dynamic quantitative analysis method based on the safety margin difference vector (SMDV) σ and a variant of the SMDV: the safety margin difference derivative vector (SMDDV) \(\sigma^{\prime}\) . The simulation results are carried out in the established engine component-level model, and the simulation results obtain the temporal feature that can accurately describe the coupling relationship of the limit protection parameters.