The present invention provides an HARQ-ACK feedback method and device. User equipment of the present invention detects downlink grant downlink control information and performs HARQ-ACK feedback for downlink data corresponding to the downlink control information. The user equipment processes HARQ-ACK for downlink data as a discontinuous transmission (DTX), when there is interference or noise exceeding a threshold value in the downlink data. Therefore, the user equipment can be prevented from receiving the downlink data having a different redundancy version.