In view of the shortcomings of airspace representation being characterized by using latitude and longitude coordinates, a method of airspace raster is proposed based on GeoSOT grid. Firstly, the airspace raster representation being concise, good in efficiency, and easy in coordination and report, some typical grid systems of the U.S. Army are analyzed. Secondly, combined with the general flight rules and flight interval regulations, a division scheme and a coding structure of grid reference system for airspace representation are designed. Finally, according to the principle of minimum grid and precision correspondence, the detailed raster representation flow of point, line and area airspace is given, and the application analysis of airspace representation scenario is carried out on grid platform. This provides a new technical means and practical ideas for the airspace representation.