To provide a work method in a narrow space of a building by a drone.SOLUTION: There is provided a work method for making a drone 10 to perform a work inside of a narrow space 2 in a building 1, the narrow space 2 comprises at least, a ceiling rear space 2a, an underfloor space 2b and a life space, the drone 10 is arranged at an initial position P0 near an inlet 6, the drone is operated in an automatic operation mode or a manual operation mode and the narrow space 2 is imaged and the drone is made to fly to a final position Pf, the drone 10 is made to perform one or more works out of following (1) to (6) and is made to restore and fly from the final position Pf to the initial position P0 then the drone is collected. The works are: (1) inspecting an internal state of the narrow space； (2) detecting a nest of an injurious bird in the narrow space； (3) detecting a noxious insect nest and/or a noxious insect in the narrow space； (4) processing for turning the injurious bird in the narrow space out； (5) ejecting a medicament to the injurious bird nest in the narrow space； (6) pest extermination processing for ejecting a medicament to the noxious insect nest and/or noxious insect in the narrow space.SELECTED DRAWING: Figure 1【課題】ドローンによる建物の狭隘空間での作業方法を提供する。【解決手段】本発明は建物１にある狭隘空間２の内部をドローン１０により作業する作業方法で、狭隘空間２は天井裏空間２ａ、床下空間２ｂ及び生活空間を少なくとも含み、入口６付近の初期位置Ｐ０にドローン１０を配置し、自動運転モード又は手動運転モードで操作して狭隘空間２を撮影して最終位置Ｐｆまで飛行させ、ドローン１０に下記（１）～（６）の一つ以上の作業を行わせ、最終位置Ｐｆから初期位置Ｐ０まで復帰飛行させて回収する。（１）前記狭隘空間の内部状態を調査、（２）前記狭隘空間に存在する害鳥獣巣を発見、（３）前記狭隘空間に存在する害虫巣及び／又は害虫を発見、（４）前記狭隘空間に存在する害鳥獣の追出処理、（５）前記狭隘空間に存在する害鳥獣巣に薬剤放出、（６）前記狭隘空間に存在する害虫巣及び／又は害虫に薬剤放出する害虫駆除処理。【選択図】図１
