Abstract: The icing prober is an important component of an aircraft icing protection system. The location of an icing prober affects the ice detection results greatly. It often takes a huge amount of work to determine the location of the icing prober in the process of aircraft design. In this paper, a method of determining the installation position of the icing prober with high efficiency is presented. The basic idea is using numerical method to obtain the volume fraction distribution of water droplets in the flow field around the aircraft without introducing the icing prober firstly. Then the water collection efficiency at the locations where the prober may be installed is yielded according to the results of the volume fraction distribution of water droplets, and it is compared with water collection efficiency on the wing. Finally the locations of the prober are given from the point of view that the prober has an early warning function. The method is then used in an airliner design, and the position suitable for prober location is given. On this basis, the prober is loaded at the corresponding position and a full numerical simulation is taken for the combining configuration of the aircraft and the prober. The simulation results show that the water collection efficiency at the position with prober is similar to that without prober, and both are larger than the value on the wing under the same condition, which means the requirements of the icing protection for early warning are met. The method can be applied to the any transport aircraft and improve the design efficiency of the icing protection system.