The invention provides a traffic prediction method based on an enhanced space-time diagram neural network, and the method comprises the steps: modeling the time correlation and spatial correlation ofa road network based on a traffic prediction framework from a sequence to a sequence model, and constructing a directed weighted graph for the whole road network according to the upstream and downstream relationship of the road network; spatial correlation of a road network is captured through a diffusion graph convolutional network, spatial correlation characteristics of the road network are extracted, a time sequence with the spatial correlation characteristics is input into a recurrent neural network to capture time correlation of the road network, and then a prediction result is optimizedin the decoding process by an actor-critic algorithm in reinforcement learning; regarding A road network relation topological graph captured by each time slice as an actor in an intelligent agent anda recurrent neural network as a random strategy of a next action selected by the actor, judging the action selected by the actor by using critic, feeding back a dominance function, and enabling the actor to update strategy parameters according to the fed-back dominance function, so that prediction precision is greatly improved compared with a traditional method.