A method for feeding back acknowledge/non-acknowledge, ACK/NACK, comprising: receiving (101, 303), by user equipment, UE, configuration information of an ACK/NACK resource, wherein the configuration information is sent by a network node, wherein the UE supports downlink transmission mode in both universal mobile telecommunications system, UMTS, and long term evolution, LTE, and supports uplink transmission mode only in the UMTS or only in the LTE; determining (102, 304, 305, 306), by the UE, the ACK/NACK resource according to the configuration information, wherein the ACK/NACK resource is a time frequency resource adapted to carry the ACK/NACK in an uplink channel; and feeding back (103, 308), by the UE, the ACK/NACK to the network node in the ACK/NACK resource, wherein the determining, by the UE, the ACK/NACK resource according to the configuration information comprises: determining, by the UE, at least one time frequency resource as a resource to be selected, from time frequency resources of the uplink channel, according to the configuration information; and acquiring, by the UE, auxiliary indication; and determining, by the UE, the ACK/NACK resource from the resource to be selected, according to the auxiliary indication, wherein the auxiliary indication comprises any one of a channel number of a high speed shared control channel, HS-SCCH, transmission power control, TPC, domain information of a dedicated physical control channel, DPCCH, TPC domain information of fractional dedicated physical control channel, F-DPCH, information carried in a control channel, information carried in a custom channel, TPC domain information of certain downlink control information, DCI, in physical downlink control channel / enhanced-physical downlink control channel, PDCCH/E-PDCCH, information of a carrier indication field, CIF, of PDCCH/E-PDCCH, or a radio network temporary identifier, RNTI. receiving (101, 303), by user equipment, UE, configuration information of an ACK/NACK resource, wherein the configuration information is sent by a network node, wherein the UE supports downlink transmission mode in both universal mobile telecommunications system, UMTS, and long term evolution, LTE, and supports uplink transmission mode only in the UMTS or only in the LTE; determining (102, 304, 305, 306), by the UE, the ACK/NACK resource according to the configuration information, wherein the ACK/NACK resource is a time frequency resource adapted to carry the ACK/NACK in an uplink channel; and feeding back (103, 308), by the UE, the ACK/NACK to the network node in the ACK/NACK resource, wherein the determining, by the UE, the ACK/NACK resource according to the configuration information comprises: determining, by the UE, at least one time frequency resource as a resource to be selected, from time frequency resources of the uplink channel, according to the configuration information; and acquiring, by the UE, auxiliary indication; and determining, by the UE, the ACK/NACK resource from the resource to be selected, according to the auxiliary indication, wherein the auxiliary indication comprises any one of a channel number of a high speed shared control channel, HS-SCCH, transmission power control, TPC, domain information of a dedicated physical control channel, DPCCH, TPC domain information of fractional dedicated physical control channel, F-DPCH, information carried in a control channel, information carried in a custom channel, TPC domain information of certain downlink control information, DCI, in physical downlink control channel / enhanced-physical downlink control channel, PDCCH/E-PDCCH, information of a carrier indication field, CIF, of PDCCH/E-PDCCH, or a radio network temporary identifier, RNTI. determining, by the UE, at least one time frequency resource as a resource to be selected, from time frequency resources of the uplink channel, according to the configuration information; and acquiring, by the UE, auxiliary indication; and determining, by the UE, the ACK/NACK resource from the resource to be selected, according to the auxiliary indication, wherein the auxiliary indication comprises any one of a channel number of a high speed shared control channel, HS-SCCH, transmission power control, TPC, domain information of a dedicated physical control channel, DPCCH, TPC domain information of fractional dedicated physical control channel, F-DPCH, information carried in a control channel, information carried in a custom channel, TPC domain information of certain downlink control information, DCI, in physical downlink control channel / enhanced-physical downlink control channel, PDCCH/E-PDCCH, information of a carrier indication field, CIF, of PDCCH/E-PDCCH, or a radio network temporary identifier, RNTI.