Methods for reserving a data channel and apparatuses supporting the same are disclosed. A method for reserving a data channel in a wireless access system includes transmitting a request frame for reserving the data channel by a sending node, and receiving a notify frame in response to the request frame during a first time period or a second time period by the sending node. If the notify frame is received during the first time period, the sending node determines that the request frame has been collided, and if the notify frame is received during the second time period, the sending node determines that the data channel has been reserved successfully.