Embodiments of the present invention provide an apparatus and a method for determining a transmission direction of a secondary carrier. A reference carrier of a first secondary carrier is obtained according to network configuration information, and a transmission direction of a subframe on the first secondary carrier is determined according to a transmission direction of a subframe on the reference carrier, so that data transmission directions of the reference carrier and the first secondary carrier are the same at a same moment. A transmission direction of data of the subframes on the first secondary carrier transmitted in a frequency band adjacent to a frequency band of the reference carrier is determined by using the reference carrier, thereby avoiding interference occurring when the adjacent frequency bands simultaneously transmit data of different directions.