With the rapid development of smart distribution network, the access of a large number of distributed generation makes the distribution network faces some new challenges. In this paper, the meaning and structure of the active distribution network are introduced firstly. Then for electric vehicles as the active load, proposed to integrate electric vehicles entity-centric hierarchical control structure. Based on the analysis of the effect and benefit of electric vehicles and its active management on the steady operation of power grid, proposed method for evaluating the impact of electric vehicles on the low voltage and medium voltage distribution network under different charging strategy, and the corresponding mathematical model and algorithm are given. The related simulation and results analysis are also carried out. It provides a theoretical basis for the active management and control of electric vehicles in the distribution network.