Method and device for data transmission, terminal, and base station

Provided in the present application are a method and a device for data transmission. The method comprises: a base station receiving channel state information reported by a terminal, the channel state information being used for indicating a first downlink channel quality of a downlink channel between the base station and the terminal and a second downlink channel quality of a downlink channel between another base station and the terminal; the base station determining, according to the high-and-low relationship between the first downlink channel quality and the second downlink channel quality, a part to be sent of downlink data that needs to be sent by the base station to the terminal; and the base station sending to the terminal the part to be sent. Using the method and device provided by the present application, the possibility of the base station experiencing downlink channel depth attenuation while sending the systematic bits and parity bits of the downlink data can be reduced, thereby improving the robustness of the transmission process of the downlink data.