The ground proximity warning envelope in TSO-C151b standard is a general model design without considering the characteristics of the aircraft. In order to accurately give the warning envelope of excessive descent rate of a certain aircraft, the alarm mechanism was analyzed by combining the aerodynamic characteristics and control characteristics of the aircraft, and a six degree of freedom simulation program was established. Based on the aircraft engine data, aerodynamic data and quality characteristics data, simulation models and operation procedures were established to simulate the operation response process of each rudder surface, as well as the motion attitude and flight path of the aircraft in real time. The loss height pulled up by the aircraft at different descent rates was calculated, and the ground proximity warning envelope was designed. The actual flight test data verified that the model design is reasonable and the calculation results are accurate. The alarm envelope obtained by simulation is compared with TSO-C151b, and the suggestions for the use of the ground proximity warning envelope are given to ensure the flight safety of the aircraft.