The　wind　resistance　of　coaxial　rotors　in　hover　is　tested　considering　the　horizontal　and　vertical　light　breezes　with　the　wind　velocity　varied　from　1.6　to　3.3　m/s　and　the　gentle　breeze　with　the　wind　velocity　varied　from　3.4　to　5.4　m/s　in　the　natural　environment.　A　velocity　distribution　model　of　blade　in　the　natural　incoming　flow　is　established,　and　a　low-speed　wind　tunnel　is　also　introduced　to　simulate　the　natural　disturbance　on　the　coaxial　rotors.　The　sliding　mesh　method　is　adopted　to　calculate　the　flow　field　and　capture　the　aerodynamic　interference　in　the　natural　incoming　flow,　mainly　including　the　distribution　of　tip　pressure,　the　streamline　distribution　of　flow　field　and　the　velocity　vector　of　blade　tip.　Results　show　that　the　proposed　simulation　method　can　accurately　reflect　the　influence　of　natural　incoming　flow　on　the　aerodynamic　characteristics　of　coaxial　rotors.　Compared　to　the　case　with　no　wind　gust,　the　performance　of　coaxial　rotors　is　declined　due　to　vertical　incoming　flow.　It　is　noted　that　the　coaxial　rotors　can　effectively　resist　the　wind　disturbance　in　the　horizontal　incoming　flow,　and　eventually　the　rotor　performance　is　greatly　improved　with　the　increase　in　wind　velocity.　©　2018,　Editorial　Board　of　Acta　Armamentarii.　All　right　reserved.