A method and an apparatus for configuring a control channel in a communication system, according to the present invention, allocate resources of different sizes according to a distributed transmission mode and a localized transmission mode and apply different antenna transmission techniques, to a control channel on the basis of frequency division. In addition, the present invention relates to a method by which a terminal estimates a channel irrespective of the transmission mode. According to the present invention, a control channel transmitted to different terminals from a base station can be efficiently multiplexed and the control channel be received faster by reducing the complexity of the terminal.