In an unmanned aerial vehicle system S, a target position Pt to which UAV 1a is headed among a plurality of UAVs 1 is determined on the basis of a position of each of a plurality of ports 2, and the UAV 1a is controlled to fly toward the target position Pt. And then, a port 2x to be used for landing of the UAV 1a is determined on the basis of a reservation status of each of the plurality of ports 2 by the other UAV 1 different from the UAV 1a among the plurality of the UAVs 1 while the UAV 1a is flying toward the target position Pt, and the UAV 1a is controlled to fly toward the determined port 2x.