A method includes receiving downlink data transmitted by a base station via a primary and secondary component carrier in a predetermined order; detecting the received downlink data to obtain indication information on correctly receiving and wrongly receiving the downlink data, or no control information received, allocating corresponding uplink resources according to the primary and secondary component carrier where the detected downlink data is present; arranging the indication information obtained through detecting according to the order of transmitting the downlink data by the base station to obtain an indication information sequence; generating an uplink response signal and determining the uplink resources used to feed back the uplink response signal; transmitting the uplink response signal to the base station using the determined uplink resources, so the base station determines the downlink data retransmitted according to the uplink response signal fed back in the uplink resources, enabling the BS avoid unnecessary data retransmission.