GNSS　information　is　vulnerable　to　external　interference　and　causes　failure　when　unmanned　aerial　vehicles　(UAVs)　are　in　a　fully　autonomous　flight　in　complex　environments　such　as　high-rise　parks　and　dense　forests.　This　paper　presents　a　pan-tilt-based　visual　servoing　(PBVS)　method　for　obtaining　world　coordinate　information.　The　system　is　equipped　with　an　inertial　measurement　unit　(IMU),　an　air　pressure　sensor,　a　magnetometer,　and　a　pan-tilt-zoom　(PTZ)　camera.　In　this　paper,　we　explain　the　physical　model　and　the　application　method　of　the　PBVS　system,　which　can　be　briefly　summarized　as　follows.　We　track　the　operation　target　with　a　UAV　carrying　a　camera　and　output　the　information　about　the　UAV’s　position　and　the　angle　between　the　PTZ　and　the　anchor　point.　In　this　way,　we　can　obtain　the　current　absolute　position　information　of　the　UAV　with　its　absolute　altitude　collected　by　the　height　sensing　unit　and　absolute　geographic　coordinate　information　and　altitude　information　of　the　tracked　target.　We　set　up　an　actual　UAV　experimental　environment.　To　meet　the　calculation　requirements,　some　sensor　data　will　be　sent　to　the　cloud　through　the　network.　Through　the　field　tests,　it　can　be　concluded　that　the　systematic　deviation　of　the　overall　solution　is　less　than　the　error　of　GNSS　sensor　equipment,　and　it　can　provide　navigation　coordinate　information　for　the　UAV　in　complex　environments.　Compared　with　traditional　visual　navigation　systems,　our　scheme　has　the　advantage　of　obtaining　absolute,　continuous,　accurate,　and　efficient　navigation　information　at　a　short　distance　(within　15　m　from　the　target).　This　system　can　be　used　in　scenarios　that　require　autonomous　cruise,　such　as　self-powered　inspections　of　UAVs,　patrols　in　parks,　etc.　©　2020　by　the　authors.　Licensee　MDPI,　Basel,　Switzerland.