the disclosure provides a method and a device for feeding back acknowledgment information during switching of backhaul link subframe configuration , and the method includes during the switching of the backhaul link subframe configuration , if uplink ack / negative ack information , which corresponds to a last transmission before the switching of one or more downlink hybrid automatic repeat request transmissions , is not fed back on a ul subframe which is before the switching , feeding back the ack / nack information on an available ul subframe which is after the switching since nms after the last transmission , wherein n is an integer . the disclosure achieves the effect of correctly feeding back the ack information during switching of the backhaul link subframe configuration .