A wind measurement system of a six-rotor unmanned aerial vehicle （UAV） equipped with an ultrasonic anemometer was developed and was used to carry out the wind field measurement on typical landforms such as coastal areas， agricultural greenhouse bases and dense building areas in tropical island areas. The results show that the ground roughness index， friction velocity， and ground roughness length all increase with the increase of field roughness. The wind profile of the coastal areas can adopt the exponential law or logarithmic law model， which is in good agree with the specified values of the landform in the Chinese Standard A and European Standard Ⅰ， and the turbulence intensity is significantly smaller than the existing standard value； the wind profile of the greenhouse base conforms to the exponential law model， in which the wind profile and turbulence intensity are in good agreement with the specified values of the landforms in the Japanese standard Type Ⅲ； the wind profile of dense building areas conforms to the exponential law model， in which the wind profile is in good agreement with the specified values of landforms in the American standard Type B and the turbulence intensity is in good agreement with the specified values of landforms in the Japanese standard Type Ⅳ. This research verifies the reliability of the wind measurement system of a six-rotor UAV， lays the foundation for the wind resistance design of engineering structures in island areas， and provides a new method for wind field observation， wind environment assessment， and wind energy resource utilization in complex landforms.