In order to test and repair a kind of airborne radio compass, a design method of universal radio compass signal simulator based on DDS IP core is proposed. Firstly, the format and characteristics of the radio compass signal are discussed. Then, the DDS IP core in the FPGA is used to synthesize the conformal radio compass simulation signal. The host computer software is developed on the Lab Windows / CVI platform to realize the humancomputer interaction function. User can set easily and flexibly on the output signal frequency, azimuth and modulation coefficients and other parameters. Finally, the design of the radio compass antenna signal simulator was tested with the oscilloscope. The test results show that the parameters can meet the design requirements, the hardware structure is compact, the FPGA logic resources are saved, and the control is more flexible.