The invention discloses a dynamic modeling and uncertainty evaluation method for a power demand response of a user. The method comprises the steps of calculating an expected load level on the basis of an elastic economic scheduling model to obtain a difference value between an expected load and an actual load; adjusting the electricity price level according to the difference value between the expected load and the actual load and adjusting the load requirements of various nodes on the basis of the elastic economic scheduling model and the new electricity price level; calculating the difference value between the expected load and the actual load again and repeating the processes until specified iteration times or until the difference value between the expected load and the actual load is lower than a set value; and evaluating the uncertainty of the user demand response on the basis of a Monte Carlo simulation method or an interval mathematical theory method. According to the method, a dynamic negative feedback model of the demand response is built, the actual effect of the demand response sis evaluated from two angles of a mathematical algorithm and a simulation algorithm, and the method is very effective and the practicability is high.