Abstract: Geographical base map is an important basic step and component of airborne geophysical thematic map; nevertheless, the previous treatment methods seem to be rather complicated. This paper analyzes the function and present situation of the thematic base map of aero geophysical exploration and introduces the spatial analysis method. With 1:250 000 public versions of terrain data, this paper discusses the idea and method of compiling the thematic base map of aerial geophysical exploration, and completes the vectorization of geographical elements. The Dazhou-Huaying survey area in Sichuan Province is chosen to perform test. It is shown that the basemap designed by this method is simple and practical and, compared with previous processing methods, it is more intelligent, and that the production results are fast and accurate and can meet the relevant precision requirements. This method provides a strong support for the accurate production of airborne geophysical thematic maps, and it is easy to use. At the same time, it also lays a foundation for the development of airborne geophysical exploration.