A method of transmitting control information by an end node in a wireless communication system supporting multi-channel transmission includes: transmitting control information to a center node on a first channel among multiple channels within a control period of a wireless frame when the first channel is in an idle state; transmitting the control information to the center node on a second channel when the first channel is not in the idle state and the second channel is in the idle state, the second channel being selected from channels other than the first channel among the multiple channels; and transmitting the control information to the center node in a subsequent wireless frame when the second channel is not in the idle state.