The method includes: learning, by a terminal, a first CQI index according to a first CQI table, and sending the first CQI index to a base station; receiving, by the base station, the first CQI index sent by the terminal device, determining a first MCS index according to the first CQI table, a first MCS table, and the received first CQI index, and sending the determined first MCS index to the terminal device; and receiving, by the terminal, the first MCS index sent by the base station, and determining a modulation order and a code block size according to the first MCS table and the received first MCS index, where the first CQI table includes an entry in which a modulation scheme is higher than 64QAM, and the first MCS table includes an entry in which a modulation scheme is higher than 64QAM.