An information sending method, applied to a network device in a communications system in which timing of a downlink frequency band and that of an uplink frequency band are asynchronized, comprising: determining, by the network device, a first receiving start time and a first sending start time, wherein the first receiving start time is a receiving time at which the network device starts to receive a signal in a first time period, and the first sending start time is a sending time at which the network device starts to send a signal in a second time period; and sending, by the network device, indication information to a terminal device, wherein the indication information is used to instruct the terminal device to determine a second sending start time, and the second sending start time is determined based on the first receiving start time and the first sending start time, wherein the second sending start time is a sending time at which the terminal device starts to send a signal in a fourth time period; wherein the sending, by the network device, indication information to a terminal device comprises: determining, by the network device, a timing advance obtained when the terminal device accesses a cell of the network device; and sending, by the network device to the terminal device, the indication information carrying a total timing advance, wherein the total timing advance comprises a sum of the timing advance and a time deviation, and the value of the time deviation is equal to the difference between the first receiving start time and the first sending start time. determining, by the network device, a first receiving start time and a first sending start time, wherein the first receiving start time is a receiving time at which the network device starts to receive a signal in a first time period, and the first sending start time is a sending time at which the network device starts to send a signal in a second time period; and sending, by the network device, indication information to a terminal device, wherein the indication information is used to instruct the terminal device to determine a second sending start time, and the second sending start time is determined based on the first receiving start time and the first sending start time, wherein the second sending start time is a sending time at which the terminal device starts to send a signal in a fourth time period; wherein the sending, by the network device, indication information to a terminal device comprises: determining, by the network device, a timing advance obtained when the terminal device accesses a cell of the network device; and sending, by the network device to the terminal device, the indication information carrying a total timing advance, wherein the total timing advance comprises a sum of the timing advance and a time deviation, and the value of the time deviation is equal to the difference between the first receiving start time and the first sending start time. determining, by the network device, a timing advance obtained when the terminal device accesses a cell of the network device; and sending, by the network device to the terminal device, the indication information carrying a total timing advance, wherein the total timing advance comprises a sum of the timing advance and a time deviation, and the value of the time deviation is equal to the difference between the first receiving start time and the first sending start time.