An accurate assessment of user demand response potential is helpful for power companies or load aggregators to rationally call demand-side resources, improve the implementation effect of demand response, and reduce the peak-valley load difference of power systems. This paper proposes a new approach based on game theory and information value to evaluate the response potential of demand-side users. Firstly, the evaluation index system of user response potential is established based on user history behaviors, user basic information, aggregator’s incentive to users, and user’s information value. Secondly, based on game theory, the total of subjective and objective weights is integrated, and the game solution of evaluation index weight is obtained. Finally, the user potential assessment results are quantified based on the fuzzy optimization set pair analysis theory to achieve an accurate online assessment of the demand-side user response potential.