Provided is a communication adapter switching method and apparatus in a system having a plurality of communication adapters. The method includes: setting the addresses of the plurality of communication adapters equal to the address of the first of the plurality of communication adapters; setting a packet filtering mode of the communication adapters other than the first communication adapter to a mode in which all packets are accepted; and switching from one of the communication adapters to another when the one communication adapter is disconnected during communication. Accordingly, seamless handoff from the wired LAN to the wireless LAN is possible, since the TCP/IP session is maintained with the same IP address.