Abstract: Aiming at the problems that are difficult to detect and find in the navigation countermeasures environment, this paper presents the design scheme and interference source search process of the satellite navigation interference source air-ground cooperative direction finding and positioning system, and conducts simulation analysis on the interference detection technology used in the system, improved spatial spectrum estimation and multi-interference source direction finding technology combined with correlation interferometer. The system is tested and verified in practice. The actual test results show that the system can simultaneously detect the number of multiple interference sources of the same frequency is 4, the direction finding accuracy is 1.4 degrees (root mean square error), the system positioning accuracy is less than 5%R (R is the distance between the interference source and the monitoring point), can meet the actual use requirements.