Embodiments disclose a multi-frequency transceiver and a base station. The multi-frequency transceiver is connected to an antenna, and includes: at least one transmit multiplexer, where each transmit multiplexer includes multiple transmit paths, and each transmit path is used to transmit one frequency band by using the antenna; and at least one receive multiplexer, where each receive multiplexer includes multiple receive paths, and each receive path is used to receive one frequency band by using the antenna.