The invention relates to an active power distribution network operating method based on electricity cost differentiation. According to the method, source and load coordinated operation control is conducted by means of a real-time electricity price and electricity cost differentiation electricity supply agreement, and a power distribution network has the flexible control ability of adjusting or interrupting loads of users who sign the differentiation electricity supply agreement by means of the differentiation electricity supply agreement which is characterized in different electricity cost levels and capable of achieving adjustment and interruption of loads. On this basis, dynamic adjustment of the load of the power distribution network can be achieved by means of electricity price with the real-time electricity pricing method based on expected load rate roll correction, and meanwhile, methods for prevention and control over the load rate based on adjustable loads and for correction control over the load rate based on interruptible loads are provided to solve the probable problem that the load rate does not meet restraint conditions during real-time electricity price adjustment. By the adoption of the operation method, the fluctuation of the load rate can be effectively restrained, load leveling can be achieved, and absorption of distributed generation and full utilization of distribution transform capacity are effectively guaranteed.