A method of load sharing, includes: extracting a factor field capable of distinguishing data flow in a packet header of the classified data flow, and taking the factor field as an input factor of a default load sharing algorithm of a network forwarding device interface, or taking the factor field as an input factor of a load sharing algorithm capable of uniformly allocating the data flows and selected according to the flow characteristic of the data flows, calculating the paths of the data flows, and forwarding the data flows according to respective paths. The method is used for increasing the expansibility of the network forwarding device and achieving load balancing.