An apparatus and method for communicating channel information in a relay wireless communication system are provided. A Base Station (BS) apparatus includes a message generator for generating a channel measurement request message to be transmitted to a Relay Station (RS) when the RS is connected; a Transmit (TX) modem for performing a physical layer processing on a message generated by the message generator and for transmitting the processed message; a message analyzer for analyzing a channel measurement response message received from the RS and for obtaining channel estimation information; and a scheduler for performing data scheduling by using the channel estimation information for a predetermined duration corresponding to a plurality of frames.