Abstract: Based on combined guided munition with SINS/GPS and homing head, the framework of hardware-in-the-loop simulation system(HILS) is designed to test the integrated navigation system and guidance and control system.The scheduler of HILS is designed, adopting the mechanism of frequency based scheduler(FBS) to ensure real-time and synchronous performance.The synchronization problem of multiple CPUs is discussed and solved.Simulations indicate that the algorithm of the navigation computer is correct and the computation delay inconsiderable, the correcting effect of GPS is satisfactory, the precision of SINS/GPS can meet the requirements of handover.The guidance and control system is properly designed and can meet the accuracy and attack angle requirement for still or mobile target.