The invention discloses a power distribution network operation efficiency evaluation method and system based on big data mining, and relates to the field of the power distribution network monitoring and control. The method comprises the following steps: collecting a power distribution network operation efficiency evaluation parameter, and establishing a power distribution network operation efficiency evaluation parameter database; constructing at least a multiple linear regression model, an exponential smoothing model, a first-order/second-order self-adaptive combination model and a neural network parameter optimization model; and evaluating and/or predicting the power distribution network operation efficiency by using the multiple linear regression model, the exponential smoothing model,the first-order/second-order self-adaptive combination model and the neural network parameter optimization model. By mining the relativity big data of the power distribution network, the distributionnetwork equipment and system operation efficiency, the coordination and the equipment equilibrium degree, the public power grid capital, and the user dedicated capital efficiency are analyzed according to different power supply regions and function zone types, and the influence factors with low efficiency are mined, thereby forming an efficient tool for distribution network efficiency monitoring,and a certain tendency pre-judgment and estimation function is provided.