Abstract: Aiming at the perturbation of gate assignment caused by flight operation in early or delay, analyzing the distribution rule of deviation between actual arrival-departure time and plan time of flights in actual operation of airport, a robust evaluation function of gate assignment based on buffer time cost was proposed. On this basis, taking the minimum of buffer time cost, gate-flight size difference and the number of remote gates as the optimization objective, a robust gate assignment model was established. At the same time, a tabu search algorithm was designed to solve the model. The results of model verification based on the actual operating data of two typical working day at Capital International Airport show that, compared with no considering robustness scheme and the traditional method of minimizing the sum of the dispersion square of gate idle time, the flight conflicts are reduced by 98.1% and 97.6% respectively on A day and reduced by 74.3% and 70.8% respectively on B day with the proposed methods, improving the robustness of the gate assignment plan effectively.