According to one embodiment of the present invention, the method for transmitting control information from a relay node to a base station on a backhaul link comprises the steps of: determining whether one time slot of a backhaul uplink subframe from the relay node to the base station is a first type slot having transmitted symbol with guard time set or a second type slot without guard time set; diffusing the control information in a time domain using a first length sequence for the first type slot or a second length sequence for the second type slot; mapping the diffused control information on at least one slot from the first type slot or the second type slot; and transmitting the backhaul uplink subframe having more than one slot from the first type slot or the second type slot wherein the control information is mapped.