The invention provides a consistency control method with a flexible load participating in active advanced scheduling. The consistency control method comprises the following steps of: considering to divide an active real-time scheduling process of the flexible load into a 5 min advanced scheduling time bucket and an AGC (Automatic Gain Control) real-time control time bucket; performing uniform optimized scheduling on a slow-speed generator set and a load agency by a scheduling center within the 5 min advanced scheduling time bucket, issuing a power adjustment amount to the load agency to perform the consistency coordinative control by acting for the internal flexible loads; carrying on adjusting the power unbalance amount in the real-time running stage of the power system by the AGC generator set within the AGC real-time control time bucket. The invention provides an effective path for the flexible lead resource which is distributed in a wide domain and can adjust the electric power rapidly to participate in the active real-time balance of the system, and is of great significance in effectively reducing the adjusting pressure of the AGC generator set, improving the qualified rate of the CPS index, copying with a small-possibility high-risk accident in the system and the like.