In order to adapt to the increasingly complex changes of the airborne electrical system structure, ensure that the electrical performance of the system is well, reduce the risk of flight test, this paper puts forward a kind of airborne electrical system hardwareintheloop simulation method. This paper uses the semiphysical simulation platform RTLAB to study brushless DC motor (BLDCM) servo system. According to the RTLAB modeling rules, the model of the motor was put up. The controller of the motor, which takes DSP TMS320F28335 as the core, and signal conditioning circuit were implemented. The control program was accomplished in CCS3.3 Hardwareintheloop simulation experiments were carried out to simulate the serve system’s dynamic performances. The dynamic response of the motor could be simulated by changing the load torque and the speed settings. Compared with digital simulation and realtime simulation, the validity and accuracy of hardwareintheloop simulation were confirmed.