A data sending method, comprising: receiving, by a terminal device, a configuration message from a network device, wherein the configuration message is used to indicate a configured grant, and the configuration message comprises information about a timer; determining, by the terminal device, that the configured grant is used for a first hybrid automatic repeat request, HARQ, process, and starting the timer for the first HARQ process, wherein to-be-sent data in the first HARQ process is data on a first logical channel; during running of the timer, when there is to-be-newly-transmitted data on a second logical channel, stopping the timer, or sending the configured grant of the first HARQ process and information about the first HARQ process to a HARQ entity of the terminal device; and sending, by the terminal device, the data that is on the second logical channel by using the configured grant; wherein stopping the timer, or sending the configured grant of the first HARQ process and information about the first HARQ process to the HARQ entity further comprises: determining an attribute parameter of the first logical channel and an attribute parameter of the second logical channel, determining whether the attribute parameter of the first logical channel and the attribute parameter of the second logical channel meet a preset condition, wherein the preset condition comprises: a cyclic prefix, CP, length of a first uplink grant resource of the first logical channel is greater than a CP length of a second uplink grant resource of the second logical channel; wherein when the preset condition is met, stopping the timer, or sending the configured grant of the first HARQ process and the information about the first HARQ process to the HARQ entity: wherein when the preset condition is not met, continuing to run the timer. receiving, by a terminal device, a configuration message from a network device, wherein the configuration message is used to indicate a configured grant, and the configuration message comprises information about a timer; determining, by the terminal device, that the configured grant is used for a first hybrid automatic repeat request, HARQ, process, and starting the timer for the first HARQ process, wherein to-be-sent data in the first HARQ process is data on a first logical channel; during running of the timer, when there is to-be-newly-transmitted data on a second logical channel, stopping the timer, or sending the configured grant of the first HARQ process and information about the first HARQ process to a HARQ entity of the terminal device; and sending, by the terminal device, the data that is on the second logical channel by using the configured grant; wherein stopping the timer, or sending the configured grant of the first HARQ process and information about the first HARQ process to the HARQ entity further comprises: determining an attribute parameter of the first logical channel and an attribute parameter of the second logical channel, determining whether the attribute parameter of the first logical channel and the attribute parameter of the second logical channel meet a preset condition, wherein the preset condition comprises: a cyclic prefix, CP, length of a first uplink grant resource of the first logical channel is greater than a CP length of a second uplink grant resource of the second logical channel; wherein when the preset condition is met, stopping the timer, or sending the configured grant of the first HARQ process and the information about the first HARQ process to the HARQ entity: wherein when the preset condition is not met, continuing to run the timer. a cyclic prefix, CP, length of a first uplink grant resource of the first logical channel is greater than a CP length of a second uplink grant resource of the second logical channel; wherein when the preset condition is met, stopping the timer, or sending the configured grant of the first HARQ process and the information about the first HARQ process to the HARQ entity: wherein when the preset condition is not met, continuing to run the timer.