Embodiments of the present invention provide a method for learning a media access control address, a network device and a system. The method includes: generating a key value according to a key field of a received packet, and obtaining an index value corresponding to the key value according to the key value; performing a linear random iteration on the index value according to a preset number of iterations; searching, according to an iteration index value obtained during a first iteration, in a MAC address pool for a MAC address corresponding to the iteration index value obtained during the first iteration; and learning a MAC address of the packet according to a search result. By using the embodiments of the present invention a media access control address space may be fully utilized, and the problem of media access control address conflicts may be solved to the greatest extent.