This paper focuses on mission planning of cooperative reconnaissance for multiple UAVs in complex environment with obstacles.Firstly,several models of sensor detection,duration time of effective reconnaissance and complex polygonal obstacles are formulated respectively for different reconnaissance missions.Secondly,a two-stage framework for mission planning of multi-UAV cooperative reconnaissance in complex environment with polygonal obstacles is established by comprehensively considering the constraints of reconnaissance duration time and obstacle avoidance.The two-stage solution effectively reduces the complexity of solving the cooperative reconnaissance problem.Finally,considering the UAV kinematic constraint,a heuristic path planning algorithm based on the greedy strategy is designed,which can obtain a flying path that is as short as possible while avoiding the polygonal obstacles at the same time.The simulation results demonstrate the effectiveness of the proposed algorithm.