In view of the defect that a conventional low-resolution radar fails to directly resolve targets flying in formation in both range and azimuth, the radar echo signals of multi-targets in formation are analyzed for time-frequency characteristics. A method is proposed, which is used for extracting the sortie information from the formation target radar echo on the basis of smoothed pseudo - WVD distribution, and such a method is used not only for identifying target sortie number reliably, but also for resisting noise and interference. The experimental results illustrate that the efficiency of the method is superior to that of the conventional WVD distribution.