An operation method of a terminal in a communication system may comprise: receiving, from a base station, a higher layer message including information indicating that first DCI including a HARQ feedback enabled/disabled indicator is configured; receiving the first DCI from the base station; receiving first downlink data from the base station based on first scheduling information included in the first DCI; and determining whether to transmit a first HARQ response for the first downlink data based on the HARQ feedback enabled/disabled indicator included in the first DCI.