Aiming at the security problem caused by the increasing peak load of distribution network with charging load, an incentive demand response (DR) is established and the response characteristics of electric vehicle (EV) users is considered. Firstly, the incentive mechanism is proposed that takes into account the effect of peak load reduction and the response degree of users. Secondly, the response characteristics are analyzed for contracted users and the model for evaluating the user's contract response times limit is proposed. The model of user response is then established with the consideration of the over response and under response. In addition, a cost and benefit model of grid company, aggregators and EV users participating in DR is established, and an optimization method of benchmark compensation price is proposed. Finally, simulations are examined to investigate the impact of the contracted users charging behaviors, the benchmark compensation price and charging power on load response. This research provides a reference for aggregators to screen contracted users, set different contract requirements, and adjust compensation electricity prices.