The invention provides a transmission method for data among OpenFlow network domains and a device. The method comprises the steps: obtaining global network information by a controller of a local network domain, wherein the global network information is information which is needed when data exchange is conducted between the local network domain and an adjacent network domain; and for a data message of which a destination address is not located in the local network domain, controlling an exchanger of the local network domain through the controller of the local network domain to transmit the data message to the adjacent network domain according to the global network information. Through the technical scheme, an effect of the data exchange among the different OpenFlow network domains can be achieved.