A method for reporting and obtaining channel state information, an eNodeB, and a user equipment are disclosed. The method for reporting channel state information includes: determining a reported content in channel state information (CSI) of downlink component carriers according to priorities of contents-in-CSI, where the CSI of the downlink component carriers includes the reported content and a content that is not to be reported; and reporting the reported content to an eNodeB on a physical uplink control channel (PUCCH). By determining a reported content in CSI according to a priority, the shortage of a CSI reporting resource may be relieved.