The invention provides a data transmission method and device based on a serial server and a serial server. The method comprises the steps that: the serial server receives a request data message sent by a control center; the serial server sends the request data message to remote network equipment, the remote network equipment carries out identification on an address identifier, and when the address identifier is the same with an address identifier of a native machine, data corresponding to the request data message is sent to the serial server; and before sending the data to the control center, the serial server sends a startup signal to an interface of a Modern. The remote network equipment can send the data only when the address identifier in the request data message is consistent with the address identifier of the native machine so as to ensure that only one piece of remote network equipment sends the data to the control center in the same time and the serial server only starts up the Modern used when the data is sent to the control center, thereby avoiding interference to interaction between the remote network equipment and the control center, which is caused in a case that all Moderns are started up.