An apparatus and a method for processing transmission information of a broadcast message constituted by a Relay Station (RS) in a multihop relay Broadband Wireless Access (BWA) communication system are provided. A communication method of the RS includes composing a message to be sent to a Mobile Station (MS); transmitting a scheduling request message which includes information required to schedule the composed message, to a Base Station (BS); and receiving an allocation message which includes information to transmit the composed message, from the BS in response to the scheduling request message.