In order to solve the difficult testing and acquiring the real interlaced signal of the automatic dependent surveillance-broadcast(ADS-B), a synthetic method of multi-target ADS-B signal is proposed. The principle of multi-target generation technology is introduced, according to ADS-B signal feature, design a digital processing method based on multi-target ADS-B intermediate frequency superimposed signal, then simulation analysis and verification were accomplished by numerical experiments. The result showed that the method could generate and simulate the superposition of multi-target signal in the space. The technology could be used to test and verify the performance and function index of the ADS-B equipment, and provide technical support for ADS-B system engineering application.