Channel state information reporting method, terminal, and base station

Embodiments of the present invention provide a channel state information (CSI) reporting method, a terminal, and a base station. A terminal obtains information of a frequency band needing to be reported, the bandwidth of the frequency band needing to be reported being less than the system bandwidth, and then reports CSI in the frequency band needing to be reported to a base station according to the information of the frequency band needing to be reported.