Disclosed are a data transmission method and device. The data transmission method comprises: after executing an LBT operation in a direction corresponding to at least one beam, a base station sending to a terminal a channel occupation request signal to request channel occupation; and after receiving a signal indicating that a channel is allowed to be occupied, the base station transmitting data on the beam sending the channel occupation request signal. The signal feedback method comprises: the terminal receiving the channel occupation request signal sent to the terminal by the base station on the at least one beam, and the channel occupation request signal is a signal for requesting channel occupation; and after correctly receiving the channel occupation request signal, the terminal feeding back, on the beam on which the signal is received, to the base station the signal indicating that the channel is allowed to be occupied.