A method for data transmission, a base station and a terminal are provided. The method for data transmission includes: configuring the number of bits occupied by downlink control information (DCI) used to indicate physical downlink shared channel (PDSCH) scheduling on each of all carriers corresponding to a to-be-scheduled terminal to be N, where N is a maximum number of bits occupied by the DCI that is used to indicate the PDSCH scheduling on a carrier configured with an aperiodic channel state information reference signal (CSI-RS); and constructing scheduling information for indicating the PDSCH scheduling based on the configured DCI, and transmitting the scheduling information to the to-be-scheduled terminal.