As a load-side resource, electric vehicles(EVs) participate in grid ancillary services and can provide efficient load adjustment capabilities, however, how to control a large number of EVs is a big problem. At present, the technology for regulating the EVs load by controlling the output power of the charging pile is relatively mature. That is, charging operators have abilitity to control the EVs directly, when the operators establish contact with the power grid dispatching center, get the dispatching command from power grid, and their charging resources can be scheduled by the command, to achieve EVs orderly charge. This paper will introduce a dispatching method for operator, that is, create charging clusters and set a control strategy to ensure the charging requirements of users, and then follow the dispatching command for upper-level dispatching between clusters and lower-level dispatching within the cluster. And besides, implement charging monitoring and optimized dispatching.