To improve the observability and locating precision of targets under electronic silence and tactic invisibility the optimal passive target tracking by multiple Unmanned Aerial Vehicles(UAVs) using Receding Horizon Optimization(RHO)was studied.With respect to optimal tracking by dual cooperative UAVs the spacial layout of the UAVs has great effect on the quality of passive target locating and tracking.To realize the optimal target tracking the RHO was used to obtain the optimal control solution and the headings of UAVs were adjusted in real time.Simulation results demonstrate the effectiveness of this method.