Embodiments of this application provide a data transmission method and apparatus. The method includes: transmitting indication information indicating a data distribution manner selected from a first data distribution manner and a second data distribution manner; performing data transmission with a terminal device according to the data distribution manner indicated by the indication information; wherein the data distribution manner indicating a distribution of modulation symbols of a code block (CB) on one or more orthogonal frequency division multiplexing (OFDM) symbols of at least one resource unit, the one or more OFDM symbols are consecutive in time-domain; and wherein modulation symbols distributed on a same OFDM symbol of the one or more OFDM symbols are interleaved in frequency-domain according to the first data distribution manner and are not interleaved in the frequency-domain according to the second data distribution manner.