A method of sending a TCI, a network-side device and a terminal device are provided. The method includes selecting, based on a link type, a channel, a RS type, or a CORESET, at least one TCI state from configured candidate TCI states, to establish a TCI state table including correspondence between the TCI state and an RS set, or correspondence among the TCI state, the RS set, and a QCL type, or correspondence between the TCI state and a channel type; sending the TCI state table and an identifier of the link type, the channel, the RS type or the CORESET corresponding to the TCI state table.