A multi-band multi-path receiving and transmitting device and method, and a base station system are provided. The multi-band multi-path receiving and transmitting device includes a broadband antenna, at least two multi-frequency couplers, a multi-band transceiver, and a signal processing module. The multi-band transceiver is adopted to decrease the number of the transceivers, thereby reducing the material cost and the mounting cost of the base station system.