Active decoy technology is an important means for radars to fight with anti-radiation missiles, which can greatly reduce the combat effectiveness of anti-radiation missiles. The shortages of low angle measurement accuracy and poor stability caused by active decoy jamming are solved based on analyzing the principle of the active decoy, to improve the effective attack capability against the enemy’s air defense and anti-missile systems. A DOA (direction of arrival) clustering sorting algorithm based on the detection of the pulse front edge is proposed to find the radar signal with leading edge, through analyzing the time-domain characteristics of flicker jamming signals. High performance and high-precision anti-jamming direction finding are realized by the proposed algorithm. The simulation results show that the technique can effectively counter the active decoy kind of four point sources.