A device management system includes a bus bar, a device management module, and a remote management module. The device management module includes at least one remotely-controllable switching circuit and a detecting circuit. When a device is installed in the rack cabinet, the remotely-controllable switching circuit connected with the device is enabled by the detecting circuit. The remote management module is in communication with the remotely-controllable switching circuit and the detecting circuit through the bus bar. The information of the device is acquired by the remote management module through the remotely-controllable switching circuit. A switch element of the remotely-controllable switching circuit which is connected to the device is selectively turned on or turned off by the remote management module. When the switch element is turned on, the DC power is transmitted to the device through the switch element.