In order to meet the requirement of the new regional aircraft electric power system(EPS) independent test,a simulator is designed to be used to simulate the relative interface function among the avionics system,engine system and the EPS.It mainly provides the simulated signals of some other systems for the EPS and indicates EPS operating status.It provides support for testing and verifying the performances of the power supply system.The result shows that under 12 different kinds of EPS statuses the simulator can provide correct control logic for ELEC PWR CPA and EPS,indicate reasonable information for EPS synopsis and EICAS and transmit information properly between generator control units and simulator by ARINC429 bus.All of the functions of the simulator are in accordance with the specifications of the aircraft and can meet the aircraft EPS test program demand.