The invention discloses a distributed formation method of an unmanned aerial vehicle cluster based on reinforcement learning. The distributed formation method comprises the steps that step (1), a formation target state function and a simulation model of environmental uncertainty factors are obtained, and an unmanned aerial vehicle formation simulation model is established; step (2), under the interference of the environmental uncertainty factors, based on the unmanned aerial vehicle formation simulation model established in the step (1), a Q learning method is adopted to train the unmanned aerial vehicle cluster to update a flight strategy table; step (3), the value of the completion degree of the formation target state is calculated according to the obtained formation target state function, the obtained value of the completion degree of the formation target state is compared with a preset value of the formation target state, whether the formation target state is reached or not is judged according to the comparison results, if the formation target state is reached, a step (4) is performed, and if not, the step (2) is entered; and step (4), the updated flight strategy table is saved. According to the distributed formation method of the unmanned aerial vehicle cluster based on reinforcement learning, flight strategy parameters with adaptability are provided for the cluster, and the stability and robustness of the unmanned aerial vehicle cluster formation are guaranteed.