Disclosed is an operation method of a centrifugal dewatering and drying system. The operation method comprises an operation method of starting the centrifugal dewatering and drying system and an operation method of stopping the centrifugal dewatering and drying system. The aim of small-differential-speed stable running is effectively achieved through a hydraulic drive centrifuge, it is guaranteed that the material dryness of a slag discharging opening of the centrifuge meets the standard, and production safety and stability are improved.