The invention, which relates to the field of the design of the demand-response electricity pricing mechanism of the power system, discloses a design method of a dynamic peak electricity pricing mechanism. The design method comprises: (1), a peak electricity price execution period is defined; (2), a date of a peak day is determined according to a peak day trigger condition and a peak day maximum allowable day number, and a peak time period is determined by using a peak day prediction load according to a fuzzy membership analysis method; and (3), a peak electricity price decision-making model is established by considering a demand response to a peak electricity price by a user, and a reasonable peak rate is set after the analysis and comparison. The provided method is suitable for the current Chinese situation and has the high maneuverability and generalizability.