A data transmission method, comprising: obtaining, by a base station, at least one clear channel assessment, CCA, detection threshold, wherein each CCA detection threshold corresponds to at least one to-be-scheduled terminal; determining, by the base station, a current CCA detection threshold from the at least one CCA detection threshold; determining, by the base station, transmit power of to-be-sent data based on the current CCA detection threshold; and sending, by the base station, the to-be-sent data to a target terminal based on the transmit power, wherein the target terminal is one of the at least one to-be-scheduled terminal, characterized in that the obtaining, by a base station, at least one CCA detection threshold comprises: obtaining, by the base station, the at least one CCA detection threshold based on a modulation and coding scheme, MCS, of the at least one to-be-scheduled terminal, by: obtaining, by the base station, the first CCA detection threshold based on a preset first adjustment step, the MCS of the at least one to-be-scheduled terminal, a maximum MCS value in a system, and a CCA detection threshold corresponding to the system; and obtaining, by the base station, the at least one CCA detection threshold based on the first CCA detection threshold, and a minimum CCA detection threshold and a maximum CCA detection threshold that are allowed by the system; wherein an MCS of each to-be-scheduled terminal in the at least one to-be-scheduled terminal is an MCS value of the to-be-scheduled terminal after adjustment by the base station by using a channel quality indicator, CQI, or an average MCS value used for scheduling the to-be-scheduled terminal on an air interface in a preset statistical time period. obtaining, by a base station, at least one clear channel assessment, CCA, detection threshold, wherein each CCA detection threshold corresponds to at least one to-be-scheduled terminal; determining, by the base station, a current CCA detection threshold from the at least one CCA detection threshold; determining, by the base station, transmit power of to-be-sent data based on the current CCA detection threshold; and sending, by the base station, the to-be-sent data to a target terminal based on the transmit power, wherein the target terminal is one of the at least one to-be-scheduled terminal, characterized in that the obtaining, by a base station, at least one CCA detection threshold comprises: obtaining, by the base station, the at least one CCA detection threshold based on a modulation and coding scheme, MCS, of the at least one to-be-scheduled terminal, by: obtaining, by the base station, the first CCA detection threshold based on a preset first adjustment step, the MCS of the at least one to-be-scheduled terminal, a maximum MCS value in a system, and a CCA detection threshold corresponding to the system; and obtaining, by the base station, the at least one CCA detection threshold based on the first CCA detection threshold, and a minimum CCA detection threshold and a maximum CCA detection threshold that are allowed by the system; wherein an MCS of each to-be-scheduled terminal in the at least one to-be-scheduled terminal is an MCS value of the to-be-scheduled terminal after adjustment by the base station by using a channel quality indicator, CQI, or an average MCS value used for scheduling the to-be-scheduled terminal on an air interface in a preset statistical time period. obtaining, by the base station, the first CCA detection threshold based on a preset first adjustment step, the MCS of the at least one to-be-scheduled terminal, a maximum MCS value in a system, and a CCA detection threshold corresponding to the system; and obtaining, by the base station, the at least one CCA detection threshold based on the first CCA detection threshold, and a minimum CCA detection threshold and a maximum CCA detection threshold that are allowed by the system; wherein an MCS of each to-be-scheduled terminal in the at least one to-be-scheduled terminal is an MCS value of the to-be-scheduled terminal after adjustment by the base station by using a channel quality indicator, CQI, or an average MCS value used for scheduling the to-be-scheduled terminal on an air interface in a preset statistical time period.