Methods and devices for reporting and issuing a band extension capability are provided. A terminal side receives terminal capability query information from a network side, determines band interval lists to which each band supported by the terminal side belongs, and reports the supported bands through cells corresponding to the band interval lists to which each band belongs; and the network side determines band interval lists to which each band supported by the network side belongs when issuing a band capability supported by the network side, and issues the supported bands through cells corresponding to the band interval lists to which each band belongs. By the solutions of the disclosure, the bands belonging to different band interval lists can be reported and issued through different cells, and the problem of limitations to the number of the bands during the reporting and issuing of the bands is solved.