Abstract: In order grasp the working characteristics of anti-icing systems of the helicopter rotor, the turboshaft engine and the inlet under icing conditions, the helicopter artificial icing tests were conducted. The icing tests were conducted in different liquid water contents, at different temperatures, and under both ground and hovering conditions. The interaction between the rotor, the engine and the inlet anti-icing systems was studied. It is found that the right inlet ices easier than the left side due to rotor rotating. The inlet has a poor anti-icing performance when the engine works under low power condition, and its performance improves when the engine power rises. The engine power condition rises after rotor icing, leading to a higher inlet temperature than that in the dry air. The periodical icing-shedding on the rotor results in an engine parameter fluctuation. The fluctuation period is hardly affected by the environmental condition, while the fluctuation amplitude changes linearly with the liquid water content.