A data transmission method, a base station, and user equipment are presented. The method includes performing rotation processing on a preset precoding matrix; performing precoding processing on to-be-sent information according to a precoding matrix obtained after the rotation processing; and sending to-be-sent information obtained after the precoding processing. In the embodiments of the present disclosure, indication information shared by a transmit end and a receive end is used to indicate whether to rotate a precoding matrix, and to-be-sent information is precoded according to the indication information. The transmit end and the receive end in this method learn the indication information in advance, and system security is improved by instructing the precoding matrix to perform flexible transformation.