Disclosed are a data transmission method and apparatus. The method includes encoding a data stream of a first receive end by using a first encoding mode, to obtain a first encoded data stream. The method also includes encoding a data stream of a second receive end by using a second encoding mode, to obtain a second encoded data stream. The method also includes encoding the first encoded data stream and the second encoded data stream by using a third encoding mode, to obtain a to-be-sent data stream. The method also includes sending the to-be-sent data stream to a corresponding receive end by using antennas.