Abstract: A 3D flight plan route is set based on an inputted scheduled flight route of an unmanned aerial vehicle. A system for setting a 3D flight plan route of an unmanned aerial vehicle according to the present invention is characterized by: inputting data indicating a scheduled flight route of the unmanned aerial vehicle on a horizontal plane; acquiring a height reference value indicating an elevation of a surface under each of a plurality of positions on the flight plan route; and determining values obtained by adding flight altitudes corresponding to the positions to the height reference values, respectively, as altitude data on the flight plan route.