Abstract: Compared with traditional surveillance system, Automatic Dependent Surveillance-Broadcast (ADS-B) system has the advantages of a high positioning accuracy, fast update rate, and low equipment cost, and thus has been vigorously promoted by the International Civil Aviation Organization. But because of its open and sharing features, the system is vulnerable to various spoofing attack which seriously threatens air traffic safety. In this paper, we propose a spoofing attack detection method using phase difference between the double antenna : for a sequence of Airborne Position Message claimed by same source, firstly, we can calculate a group of variables to indicate the directional change based on its broadcast content; secondly, we can use the phase difference to compute another group of variables as the reflection of the directional change; finally, we calculate the Pearson correlation coefficient of the two groups of variables to determine whether the target is a real aircraft or a ghost one. Inaddition, considering the false ADS-B messages that are the same as the airborne real target ICAO addresses may result in false detections, we propose a source consistency detection method. Compared with other methods, this method does not need to estimate the direction of the signal, and it is robust to the amplitude and phase error of the array, and the simulation experiments and practical data have verified the effectiveness of the method.