The invention discloses a dynamic network resource reservation QoS guaranteeing method oriented to an industrial SDN. The method comprises a reserved resource application process, a reserved resource forwarding process and a reserved resource releasing process. A data packet with a designated Ethernet type is used for performing the negotiation of the resource reservation between a terminal device and a network, a network switch connected with the terminal intercepts the data packet of this type and sends the same to a controller; the controller reserves a bandwidth resource for the data flow according to the bandwidth and delay requirement of the data flow and the actual application condition of the network bandwidth, or releases the reserved bandwidth resource, and delivers the reserved resource result to the switch in a flow table sending way to be executed. The resource reservation/releasing process is flexibly controlled through a negotiation mechanism, and the supportability on the service data flow especially the period service data flow and the adaptability on the complicated communication state by the network can be improved.