Embodiments of the present invention provide a data transmission method and apparatus. The method includes generating a configuration message. The configuration message is used to configure, for user equipment UE, a function of receiving downlink bundled data, and the downlink bundled data is downlink data that is repeatedly transmitted at least twice. The configuration message to the UE and the downlink bundled data are sent to the UE. According to the data transmission method and apparatus provided in the embodiments of the present invention, downlink data is sent to user equipment in a downlink bundling manner, thereby shortening a delay of the downlink data transmission. If the downlink data is PDCCH control signaling, timeliness of an operation indicated by the PDCCH control signaling is improved.