A dynamic network load regulating device includes a first network bridge, a second network bridge, a third network bridge, and a traffic monitoring module. The second network bridge and the third network bridge are further coupled to a plurality of terminal devices. Each of the network bridges includes a plurality of ports. The traffic monitoring module is configured to monitor the plurality of ports traffic load. When a first data transmission path traffic load reaches a congestion threshold, the dynamic network load regulating device increases the first data transmission path cost to select a second data transmission path to transmit network data. A method for the dynamic network load regulating device is also provided.