A method for transmitting Acknowledgement/Negative Acknowledgement, ACK/NACK, information at a User Equipment, UE, in a wireless communication system supporting Long Term Evolution, LTE, system and being configured to use Physical Uplink Control Channel, PUCCH, format 3 for transmitting ACK/NACK information, the method comprising: determining whether transmission of a scheduling request is configured in one uplink subframe in which ACK/NACK information for downlink transmission in a downlink subframe set including M downlink subframes is to be transmitted, where M≥1; and transmitting the ACK/NACK information and the scheduling request using PUCCH format 1a/1b in the one uplink subframe, when transmission of the ACK/NACK information coincides with the one uplink subframe for the transmission for the scheduling request and at least one of specific conditions is met, wherein the specific conditions comprise: a first condition that the ACK/NACK information acknowledges reception of two signals including one Physical Downlink Shared Channel, PDSCH, without a corresponding Physical Downlink Control Channel, PDCCH, received only on a Primary Cell, PCell, in the downlink subframe set and another PDSCH indicated by detection of corresponding another PDCCH received only on the PCell in the downlink subframe set, wherein the corresponding another PDCCH has a Downlink Assignment Index, DAI, corresponding to '00', a second condition that the ACK/NACK information acknowledges reception of two signals including the one PDSCH without the corresponding PDCCH received only on the PCell in the downlink subframe set and a Semi-Persistent Scheduling, SPS, release PDCCH having a DAI corresponding to '00'. determining whether transmission of a scheduling request is configured in one uplink subframe in which ACK/NACK information for downlink transmission in a downlink subframe set including M downlink subframes is to be transmitted, where M≥1; and transmitting the ACK/NACK information and the scheduling request using PUCCH format 1a/1b in the one uplink subframe, when transmission of the ACK/NACK information coincides with the one uplink subframe for the transmission for the scheduling request and at least one of specific conditions is met, wherein the specific conditions comprise: a first condition that the ACK/NACK information acknowledges reception of two signals including one Physical Downlink Shared Channel, PDSCH, without a corresponding Physical Downlink Control Channel, PDCCH, received only on a Primary Cell, PCell, in the downlink subframe set and another PDSCH indicated by detection of corresponding another PDCCH received only on the PCell in the downlink subframe set, wherein the corresponding another PDCCH has a Downlink Assignment Index, DAI, corresponding to '00', a second condition that the ACK/NACK information acknowledges reception of two signals including the one PDSCH without the corresponding PDCCH received only on the PCell in the downlink subframe set and a Semi-Persistent Scheduling, SPS, release PDCCH having a DAI corresponding to '00'. a first condition that the ACK/NACK information acknowledges reception of two signals including one Physical Downlink Shared Channel, PDSCH, without a corresponding Physical Downlink Control Channel, PDCCH, received only on a Primary Cell, PCell, in the downlink subframe set and another PDSCH indicated by detection of corresponding another PDCCH received only on the PCell in the downlink subframe set, wherein the corresponding another PDCCH has a Downlink Assignment Index, DAI, corresponding to '00', a second condition that the ACK/NACK information acknowledges reception of two signals including the one PDSCH without the corresponding PDCCH received only on the PCell in the downlink subframe set and a Semi-Persistent Scheduling, SPS, release PDCCH having a DAI corresponding to '00'.