A radio repeater including at least first and second relay systems, each including a reception antenna configured to receive a radio signal, a loop interference suppressor, connected to the reception antenna, configured to suppress a loop interference signal in the received radio signal from said reception antenna, an amplifier configured to amplify the loop interference-suppressed radio signal from the loop interference suppressors, and a transmission antenna having a polarization characteristic, which is orthogonal to a polarization characteristic of said reception antenna, configured to transmit the output of said amplifier.