A flight interference apparatus enabling it to block intrusion by a miniature unmanned aerial vehicle which is remotely piloted by radio communication into an area to be protected, suppress influence on communication within and outside the area, and reduce the number of required antenna devices. The flight interference apparatus includes one or a plurality of antenna devices which radiate a jamming signal from a directional antenna, and the directional antenna includes a radiating element which radiates a jamming signal of a predetermined frequency band and a reflector which gives directionality to the jamming signal in its radiation direction.