The invention discloses an agile response method for demand side frequency emergency control of a super-large-scale power grid in the technical field of power systems, which comprises millisecond-level active response, reliable delay response and optimal dynamic control, wherein the millisecond-level active response is carried out in an active response form of local side zero communication, zero communication is carried out in the phase-one response process, and the fastest response speed can reach the millisecond level; the reliable response is obtained by repeatedly confirming the frequencydip fact by a delay of 3-5 seconds so as to supplement the residual active deficit; if the control cost is lower than the standby load at the power generation side and the frequency is still lower than the rated value, the system accurately cuts off the load in a communication mode, and the frequency is restored to the rated frequency in an optimal dynamic characteristic. The method has rapidnessand reliability and can complete the staged local side active response at the same time, zero communication is carried out in the response process, the highest response speed of the demand side load resources can reach the millisecond level, and the scheme has higher reliability compared with a single-stage response scheme.