The present invention relates to a data transmitting method using a bandwidth request channel and a user terminal and a base station conducting the same. The present invention provides a communication method by a user terminal which transmits data to a base station via a bandwidth request channel, including: generating a preamble for bandwidth request; determining whether a message for the bandwidth request is generated; generating a first signal value to be operated with the preamble when it is determined that the message is generated and generating a second signal value to be operated with the preamble when it is determined that the message is not generated; operating the preamble with the generated first signal value or second signal value; and transmitting a signal including the operated preamble to the base station, thereby reducing overhead occurring when the bandwidth request information is demodulated.