Firstly, according to airworthiness regulation on anti-icing protection activation, the wing anti-icing automatic activation function is provided, including anti-icing detection, inhibition of ta-keoff, inhibition of temperature, the functions of crew operation command and engine bleed status. Secondly, the combinational logic circuit of automatic activation based on primary ice detection is designed, and the logic truth table is derived. Thirdly, the simulink model of Matlab is adopted to solve the digital verification of automatic activation function logic.The work wave validated by numerals is compliance with the truth table. The result shows the logic circuit of automatic activation is able to meet the wing anti-icing auto activation function.