To solve the problem that how to improve the performance of STAP in the environment of complex active jamming, an improved adaptive beams formed method based on the part space adaptive array processing is put forward .The method is presented, which is a method of special anti-jamming technique in series with filtering clutter using STAP technique. At first, MUSIC method is used to estimate DOA of the active jamming, then, multi-beams are formed on the anticipant and interfered directions. Finally STAP technique is used to suppress clutter after anti-interference filtering in the space. The result of simulation demonstrates that the use of this method can effectively estimates active jamming's orientation, and maintains the performance of clutter suppression in the environment of interference. Using adaptive filter in the beam domain can reduce the required computations. The efficiency of the method is demonstrated by simulation.