Dense false-target jamming can reduce the probability of target detection,and produce the oppressive and deceptive effect on radar target tracking.Aiming at the problem,a technique against dense false-target jamming based active and passive radars data fusion is proposed.Firstly,the measurement data from active radar jammed by dense false-target jamming is pre-processed.Then,associated disposal is made to the pre-processed data and measurement data from passive radar.The associated measurement pairs are kept,and the equivalent measurements are obtained using the least square method.Finally,target tracking is carried out by using the equivalent measurements.The technique makes full use of the advantages of active and passive radars,eliminates the influence of dense false targets,and realizes true-target tracking.The technique is also applicable to the case of no jamming.Simulation results verify the validity of the proposed technique.