Abstract: The airport noise isoline map plays an important role in airport noise control and airport planning. After studying airport noise characteristics and distribution, an airport noise isoline tracking algorithm based on route grid is proposed. By constructing an effective grid and creating route grid with the point code sum, the next equivalent point can be determined definitely in isoline tacking. The proposed algorithm can generate the isoline map rapidly by avoiding open isoline tracking first and then closed one Experimental results show that the proposed algorithm has more efficient performance, and generates the better airport noise isoline map, especially with no cross between isolines.