According to an example, in a method and an apparatus for expanding member ports of a link aggregation group between clusters, each apparatus in a cluster receives a port joining link aggregation group message sent by a master control board on a master apparatus in the cluster. In response to an apparatus determining that a newly joined port is a port on the apparatus itself and also is the first member port in the link aggregation group of the cluster, the newly joined port is associated with the link aggregation group. By applying the method and the apparatus for expanding member ports of a link aggregation group between clusters in this manner, according to an example, the number of member links in the link aggregation group between clusters is able to be increased, and the robustness of the network interconnection between clusters is also able to be enhanced.