Aiming at the key problem of limited computing power of the system onboard UAVs, a trajectory planning method based on real-time octree map is proposed for indoor autonomous exploration.Firstly, the depth images obtained by the RGB-D camera are used as input to construct the octree map in real time.At the same time, the octree map in the current field of view of the UAV is scanned in real time for scene recognition.Based on the scene of autonomous recognition, a method for planning the next target point in different scenes is specifically designed, which effectively reduces the amount of airborne calculations, and realizes autonomous exploration of unknown indoor environments.The simulation experiment results show that the method has advantages on feasibility and computational complexity.