Abstract: The high penetration of new energy increases the uncertainty and fluctuation of power system, while the insufficient flexibility of power system significantly affects the accommodation of new energy and the safe operation of power grid. From the perspective of flexibility resource output characteristics and the flexibility supply capacity, a source-load-storage coordinated rolling dispatch model is established based on the power system flexibility margin index, which takes the maximum peak regulation benefit, the maximum wind power consumption, the minimum units operating cost and the minimum interruptible load cost as the objectives, and comprehensively considers the operational constraints of the power system. Based on the philosophy of coordinated dispatch, the output of each flexible resource in each period was optimized, and then the output and status of each flexible resource were revised by using the super short-term wind power forecast data. Finally, a case study is made to verify the feasibility of the proposed dispatch method.