Abstract: A radio frequency apparatus and a radio frequency identification (RFID) tag detection method are provided. The radio frequency apparatus includes a reader and an RFID tag. The reader includes a first coil and a plurality of second coils. The first coil supports a first frequency band. Each second coil supports a second frequency band. The second frequency band is different from the first frequency band, and the second coils are spaced away from each other and do not overlap each other. The RFID tag includes a first and a second radio frequency circuits which supports the first frequency band and the second frequency band respectively. The first radio frequency circuit can communicate with the first coil by using the first frequency band. The second radio frequency circuit can communicate with at least one of the second coils by using the second frequency band.