Demand response potential detection is essential to promote the effect of demand response activities and further enhance the operational stability of the power grid. In this article, we establish a demand response potential detection model including estimating the loads of main network and residential customers based on similar date matching, where a mathematical program is formulated to determine the parameters in the formula of date distance, and measuring the similarity between the main network and customers during the peak and valley period, where a measure of matching degree is put forward innovatively. Customer profiles are then established based on load profile pattern, electricity consumption quantity and demand response willingness. In addition, case studies based on smart meter data of residential customers in Yuhang District, Hangzhou, Zhejiang, China, validate the effectiveness of our model.