A method for transmitting/receiving resource allocation information in a mobile communication system using a shared control channel. The transmission method includes performing scheduling for resource allocation to a plurality of terminals; generating, in a bitmap, information indicating allocation/non-allocation of resources which are not sequentially allocated beginning from a particular terminal using the scheduling result; and transmitting, over the shared control channel, resource allocation information including a terminal identifier and a resource allocation bitmap of each terminal. The reception method includes receiving from a wireless network a shared control channel including resource allocation information; determining whether a terminal identifier included in the resource allocation information is equal to a terminal identifier of the terminal; and updating a size of an available resource set according to a resource allocation bitmap for reception of next resource allocation information, if the included terminal identifier is not equal to the terminal identifier of the terminal.