Embodiments of the present disclosure disclose a precoding configuration method, device, and system. The precoding configuration method includes: generating precoding configuration information, where the precoding configuration information is used to configure a width of a frequency band for same precoding; and sending the precoding configuration information. The embodiments of the present disclosure further provide a transmit end device, a receive end device, and the precoding configuration system. In the precoding configuration method provided in the embodiments of the present disclosure, the precoding configuration information is generated and sent, so that a receive end can determine, based on the precoding configuration information, the width of the frequency band for same precoding. In the prior art, the width of the frequency band for same precoding is determined based on only system bandwidth, while the width of the frequency band for same precoding can be flexibly determined in the technical solutions provided in the embodiments of the present disclosure, so that requirements of a wireless communications system can be met in diversified scenarios, and system performance can be effectively optimized in different scenarios.