Abstract: The GNSS/inertial navigation system (INS) integrated navigation has gradually become the mainstream navigation mode due to its high precision and anti-interference capability. The reliability of airborne navigation systems is directly related to the operational safety of aircraft; therefore, it is necessary to test the system performance under extreme scenarios to ensure its airworthiness compliance. To address the requirement of performance verification under extreme scenarios that are difficult to reproduce in actual flight processes, a test and evaluation system is developed by combining simulation technology with Monte Carlo experiments, with reference to the latest performance specifications for GNSS/INS integrated navigation systems issued by the Radio Technical Commission for Aeronautics (RTCA). Based on flight data, this system constructs sensor error models under extreme scenarios such as satellite faults and ionospheric anomalies. Through automatic random superposition of different flight phases and extreme scenarios, it realizes comprehensive accuracy and integrity performance evaluation of the GNSS/INS integrated navigation system. Furthermore, it automatically statistically analyzes test results with the support of time synchronization and generates test reports, which can significantly enhance the efficiency and credibility of airworthiness compliance verification while reducing testing costs.