This application provides a data transmission method and apparatus, to determine a TC-state used for data transmission and correctly receive downlink data, thereby improving data transmission efficiency. The method includes: receiving a first physical downlink control channel (PDCCH), where the first PDCCH is used to schedule a first physical downlink shared channel (PDSCH); receiving a downlink signal by using a first transmission configuration indicator state (TC-state); obtaining a time interval between the first PDCCH and the first PDSCH; and if the time interval is less than a preset threshold, obtaining the first PDSCH from the downlink signal.