Based on the principle of maximum entropy, this paper conducts the goal planning modeling of the whole evaluation system, studies the selection of the airport's dominant goods, and verifies the applicability of the model by the case of Guangzhou Baiyun International Airport. On the basis of the current development of domestic and international air cargo, the importance of the structure of the airport's dominant cargo is explained. Then the model of airport dominant cargo selection is constructed on the basis of the principle of maximum entropy. According to the selection model, the empirical analysis of the main cargo types of Guangzhou Baiyun International Airport is conducted. Finally, according to the final evaluation value of each indicator, the dominant goods of the airport are selected to achieve reasonable allocation of limited resources so as to make corresponding proposals, to improve the overall economic efficiency of the airport, and to optimize airport development.