A feedback information transmission method, comprising: generating, by the first terminal, a sidelink HARQ-ACK codebook based on a time domain position of a resource pool of a sidelink channel, wherein the sidelink channel includes a physical sidelink shared channel or a physical sidelink feedback channel; and sending, by the first terminal, the sidelink HARQ-ACK codebook via a physical uplink control channel or a physical uplink shared channel within a target time unit for sending sidelink HARQ-ACK information within the target time unit, wherein the sidelink HARQ-ACK codebook includes sidelink HARQ-ACK information corresponding to at least one sidelink data, and wherein the sidelink HARQ-ACK information is configured to indicate a receiving state corresponding to the sidelink data, and the sidelink data is physical layer data sent by the first terminal via a sidelink, and wherein the target time unit is a time slot m, with m being a positive integer, the method further comprises: receiving a first time-interval set configured by an access network device via higher layer signaling, wherein the first time-interval set includes a set of a time slot where an end symbol of the sidelink channel is located and slot offsets k i with which the sidelink HARQ-ACK codebook is fed back, both i and k i being positive integers; traversing a plurality of slot offsets k i in the first time-interval set, and determining, for each time slot m-k i, a number of one or more PSSCHs allowed to be sent in the time slot m-k i; and for each of a plurality of resource pools of the first terminal, based on the number of one or more sidelink channels allowed to be sent in the time slot m-k i, determining a number of bits of sidelink HARQ-ACK information generated in correspondence to each time slot of the resource pool. generating, by the first terminal, a sidelink HARQ-ACK codebook based on a time domain position of a resource pool of a sidelink channel, wherein the sidelink channel includes a physical sidelink shared channel or a physical sidelink feedback channel; and sending, by the first terminal, the sidelink HARQ-ACK codebook via a physical uplink control channel or a physical uplink shared channel within a target time unit for sending sidelink HARQ-ACK information within the target time unit, wherein the sidelink HARQ-ACK codebook includes sidelink HARQ-ACK information corresponding to at least one sidelink data, and wherein the sidelink HARQ-ACK information is configured to indicate a receiving state corresponding to the sidelink data, and the sidelink data is physical layer data sent by the first terminal via a sidelink, and wherein the target time unit is a time slot m, with m being a positive integer, the method further comprises: receiving a first time-interval set configured by an access network device via higher layer signaling, wherein the first time-interval set includes a set of a time slot where an end symbol of the sidelink channel is located and slot offsets k i with which the sidelink HARQ-ACK codebook is fed back, both i and k i being positive integers; traversing a plurality of slot offsets k i in the first time-interval set, and determining, for each time slot m-k i, a number of one or more PSSCHs allowed to be sent in the time slot m-k i; and for each of a plurality of resource pools of the first terminal, based on the number of one or more sidelink channels allowed to be sent in the time slot m-k i, determining a number of bits of sidelink HARQ-ACK information generated in correspondence to each time slot of the resource pool. receiving a first time-interval set configured by an access network device via higher layer signaling, wherein the first time-interval set includes a set of a time slot where an end symbol of the sidelink channel is located and slot offsets k i with which the sidelink HARQ-ACK codebook is fed back, both i and k i being positive integers; traversing a plurality of slot offsets k i in the first time-interval set, and determining, for each time slot m-k i, a number of one or more PSSCHs allowed to be sent in the time slot m-k i; and for each of a plurality of resource pools of the first terminal, based on the number of one or more sidelink channels allowed to be sent in the time slot m-k i, determining a number of bits of sidelink HARQ-ACK information generated in correspondence to each time slot of the resource pool.