In the method, the network device sends first signaling to a first terminal device, the first signaling is used to instruct the first terminal device to perform, on an unlicensed spectrum, a listen before talk LBT procedure used for occupying an unlicensed frequency band, and send uplink information within a first time length on the unlicensed frequency band; the network device receives, on the unlicensed spectrum, the uplink information from the first terminal device within the first time length, where the first time length is a part of maximum channel occupancy time obtained by the first terminal device on the unlicensed spectrum, and the first time length is less than the maximum channel occupancy time.