A method for sending a Hybrid Automatic Repeat Request, HARQ, feedback codebook in a HARQ-ACK multiplexing scenario, comprising: detecting, by a terminal (10, 1600, 1800), downlink control information, DCI, in a plurality of time units corresponding to at least one carrier, wherein a type of the DCI is a first DCI type or a second DCI type, the first DCI is used to indicate to feed back code block group, CBG,-level hybrid automatic repeat request-acknowledgment, HARQ-ACK, information for data scheduled by using the first DCI, and the second DCI is used to indicate to feed back transport block, TB,-level HARQ-ACK information for data scheduled by using the second DCI; and sending, by the terminal (10, 1600, 1800), a HARQ-ACK feedback codebook to a network device (20, 1500, 1700), wherein the HARQ-ACK feedback codebook comprises HARQ-ACK information of at least one piece of data scheduled by using the DCI, wherein the HARQ-ACK feedback codebook is determined according to the type of the DCI and a type of the HARQ-ACK feedback codebook, and the type of the HARQ-ACK feedback codebook is a semi-persistent type or a dynamic type, wherein if first data is scheduled according to the first DCI, the first M1 bits in N1 bits that are in the HARQ-ACK feedback codebook and that correspond to the first data are code block group, CBG,-level HARQ-ACK information of the first data, and the following (N1-M1) bits in the N1 bits are negative acknowledgments, NACKs, wherein N1 is a maximum quantity of CBGs configured by the network device (20, 1500, 1700) for the first data, and M1 is a quantity of CBGs actually comprised in the first data; and if second data is scheduled according to the second DCI, the first bit in N2 bits in the HARQ-ACK feedback codebook that correspond to the second data is TB-level HARQ-ACK information of the second data, and each of the following (N2-1) bits in the N2 bits is a NACK or TB-level HARQ-ACK information, wherein N2 is a maximum quantity of CBGs configured by the network device (20, 1500, 1700) for the second data, wherein the first data is any data that is in the at least one piece of data and that is scheduled according to the first DCI, and the second data is any data that is in the at least one piece of data and that is scheduled according to the second DCI. detecting, by a terminal (10, 1600, 1800), downlink control information, DCI, in a plurality of time units corresponding to at least one carrier, wherein a type of the DCI is a first DCI type or a second DCI type, the first DCI is used to indicate to feed back code block group, CBG,-level hybrid automatic repeat request-acknowledgment, HARQ-ACK, information for data scheduled by using the first DCI, and the second DCI is used to indicate to feed back transport block, TB,-level HARQ-ACK information for data scheduled by using the second DCI; and sending, by the terminal (10, 1600, 1800), a HARQ-ACK feedback codebook to a network device (20, 1500, 1700), wherein the HARQ-ACK feedback codebook comprises HARQ-ACK information of at least one piece of data scheduled by using the DCI, wherein the HARQ-ACK feedback codebook is determined according to the type of the DCI and a type of the HARQ-ACK feedback codebook, and the type of the HARQ-ACK feedback codebook is a semi-persistent type or a dynamic type, wherein if first data is scheduled according to the first DCI, the first M1 bits in N1 bits that are in the HARQ-ACK feedback codebook and that correspond to the first data are code block group, CBG,-level HARQ-ACK information of the first data, and the following (N1-M1) bits in the N1 bits are negative acknowledgments, NACKs, wherein N1 is a maximum quantity of CBGs configured by the network device (20, 1500, 1700) for the first data, and M1 is a quantity of CBGs actually comprised in the first data; and if second data is scheduled according to the second DCI, the first bit in N2 bits in the HARQ-ACK feedback codebook that correspond to the second data is TB-level HARQ-ACK information of the second data, and each of the following (N2-1) bits in the N2 bits is a NACK or TB-level HARQ-ACK information, wherein N2 is a maximum quantity of CBGs configured by the network device (20, 1500, 1700) for the second data, wherein the first data is any data that is in the at least one piece of data and that is scheduled according to the first DCI, and the second data is any data that is in the at least one piece of data and that is scheduled according to the second DCI.