This application provides a packet forwarding method and a related apparatus. The method includes: determining whether a flow to which a packet belongs meets a large flow condition; and if the flow to which the packet belongs meets the large flow condition and a flowlet routing table does not include a flowlet entry corresponding to the flow, creating the corresponding flowlet entry in the flowlet routing table, and forwarding the packet based on the created flowlet entry. In the foregoing technical solution, a corresponding flowlet entry may be created only for a large flow, to perform flowlet-based load balancing on the large flow. This can reduce an entry resource used for flowlet-based load balancing, improve balance of multi-path load sharing, and effectively improve a traffic sharing effect of load balancing.