A method and an apparatus for performing Transmission Control Protocol (TCP) communication at a network node in a wireless communication system are provided. The method includes receiving, by the network node that connects between a Mobile Station (MS) and a data network, a TCP KeepAlive packet for maintaining a TCP connection established between a correspondent node and the MS through the data network from the correspondent node, transmitting, by the network node, when it is determined that the MS is in an idle mode upon receiving the TCP KeepAlive packet, an acknowledgement packet in response to the TCP KeepAlive packet to the correspondent node, and transmitting, by the network node, indication information indicating the reception of the TCP KeepAlive packet to the MS.