A method, device, and system for implementing load balancing are provided, and are applied to a 4-node network structure. Every two nodes in the 4-node network structure are interconnected, and the nodes are, for example, dies. The 4-node network structure includes a source node and a destination node. The method includes: When a bandwidth occupied by ingress traffic flowing into the source node and destined for the destination node is greater than a bandwidth of a fabric side link between the source node and the destination node, the source node selects at least two transmission paths to send the ingress traffic to the destination node; and when the bandwidth occupied by the ingress traffic is less than or equal to the bandwidth of the fabric side link between the source node and the destination node, the source node transmits the ingress traffic on a direct link between the source node and the destination node. This method can save network resources while implementing non-blocking switching of traffic, and meet a low-network delay requirement to some extent.