Disclosed are a data transmission method and apparatus. In embodiments of this application, a virtual cell comprising multiple cells can be configured, and data transmission can be implemented by time-division multiplexing among the cells, so that transmission carriers for a terminal service can be flexibly adjusted. Particularly, under the condition that transmission is deployed on an unlicensed spectrum resource, multiple cells operating on an unlicensed frequency band are aggregated into one virtual cell, and data transmission is implemented by time-division multiplexing among the cells; therefore, the interference in different frequency domains can be reduced and the system transmission efficiency can be improved.