A radio receiver is provided with a beam-width-variable antenna that receives a radio signal and is capable of changing the beam-width; an interference canceler for removing interference waves from the received radio signal and outputting an interference-wave-removed signal; a measuring device for measuring reception quality of the received signal based on the interference-wave-removed signal; and a beam-width controller for controlling the beam-width of the beam-width-variable antenna based on the reception quality from the measuring device.