The utility model relates to a multi-machine parallel control system of a dual-mode energy storing device. The control system comprises a station-level monitoring machine and at least two energy storing devices. Each energy storing device comprises a controller, a transformer and a battery management unit. The controller is connected with the battery management unit in a communication way. The transformer is used for being connected with a power grid via an AC bus. The controller of one of the energy storing devices acts as a primary controller selected by the station-level monitoring machine, and the rest act as secondary controllers. The primary controller and the secondary controllers are all connected with the station-level monitoring machine in the communication way via an Ethernet interface. The primary controller is connected with each secondary controller via a coordination control bus, a starting and stopping signal interface and an optical synchronization signal interface. The primary controller is connected with a load power sampling loop. A problem that a multi-machine parallel working process of an existing energy storing device is not reliable is solved.