Abstract: The source data of oversea multi-source geological thematic maps are mainly collected from public purchases, websites or international exchanges. According to the Guide of the Global Geological and Mineral Resources Database Construction compiled by the China Geological Survey, database technology with ArcGIS software is used to effectively manage and apply overseas multi-source geological map data. In this paper, several key issues such as data format conversion, map projection, geographic registration and spatial correction in the application of multi-source geological thematic map data are discussed and research.