A feedback channel receiving method, the method performed by a first terminal device, the method comprising: obtaining, by the first terminal device, configuration information of a sidelink resource pool from a network device, wherein the sidelink resource pool is used for sidelink communication between the first terminal device and a second terminal device, the configuration information is used to indicate that frequency domain resources of the resource pool comprise L sub-channels and each of the L sub-channels comprises q resource blocks RBs, the L sub-channels comprise M sub-channels and N sub-channels, the M sub-channels are used by the first terminal device to send a physical sidelink control channel PSCCH and/or a physical sidelink shared channel PSSCH, the N sub-channels are used by the first terminal device to receive a physical sidelink feedback channel PSFCH from the second terminal device, and there is a one-to-one mapping correspondence between the M sub-channels and N·q RBs comprised in the N sub-channels, wherein N·q ≥M, and L, M, N, and q are all integers greater than or equal to 1; sending, by the first terminal device, a first PSCCH and/or a first PSSCH on a first channel in a slot n to the second terminal device, wherein the first channel comprises one of the M sub-channels; determining, by the first terminal device based on the one-to-one mapping correspondence and the first channel, one of the N·q RBs comprised in the N sub-channels that corresponds to one of the M sub-channels as a first RB on which a first PSFCH is sent by the second terminal device for the first PSCCH and/or the first PSSCH received from the second terminal device; and receiving, by the first terminal device, the first PSFCH from the second terminal device on the first RB in a slot n+k, wherein n≥0, k≥1, and both n and k are integers; characterized in that wherein L, q, M, and N satisfy N = L / 1 + q, L=M+N, and ┌ ┐ represents rounding up. obtaining, by the first terminal device, configuration information of a sidelink resource pool from a network device, wherein the sidelink resource pool is used for sidelink communication between the first terminal device and a second terminal device, the configuration information is used to indicate that frequency domain resources of the resource pool comprise L sub-channels and each of the L sub-channels comprises q resource blocks RBs, the L sub-channels comprise M sub-channels and N sub-channels, the M sub-channels are used by the first terminal device to send a physical sidelink control channel PSCCH and/or a physical sidelink shared channel PSSCH, the N sub-channels are used by the first terminal device to receive a physical sidelink feedback channel PSFCH from the second terminal device, and there is a one-to-one mapping correspondence between the M sub-channels and N·q RBs comprised in the N sub-channels, wherein N·q ≥M, and L, M, N, and q are all integers greater than or equal to 1; sending, by the first terminal device, a first PSCCH and/or a first PSSCH on a first channel in a slot n to the second terminal device, wherein the first channel comprises one of the M sub-channels; determining, by the first terminal device based on the one-to-one mapping correspondence and the first channel, one of the N·q RBs comprised in the N sub-channels that corresponds to one of the M sub-channels as a first RB on which a first PSFCH is sent by the second terminal device for the first PSCCH and/or the first PSSCH received from the second terminal device; and receiving, by the first terminal device, the first PSFCH from the second terminal device on the first RB in a slot n+k, wherein n≥0, k≥1, and both n and k are integers; characterized in that wherein L, q, M, and N satisfy N = L / 1 + q, L=M+N, and ┌ ┐ represents rounding up.