A method and apparatus for calibrating multiple antennas in a radio communication device. The radio communication device is configured with a TX circuit and a RX circuit for each of the multiple antennas, each pair of the TX circuit and the RX circuit are operably coupled to the corresponding antenna in normal antenna operation. The apparatus comprises a first TX oscillator and a first RX oscillator. The first TX oscillator is operably coupled to the respective TX circuits to supply them with a TX working frequency or a RX calibrating frequency, the TX working frequency is supplied in the normal antenna operation and an antenna TX calibration operation, and the RX calibrating frequency is supplied in an antenna RX calibration operation. The first RX oscillator is operably coupled to the respective RX circuits to supply them with a RX working frequency or a TX calibrating frequency.