The Database of Geological Environmental Map System of China is China's first national database with uniform structure, format and codes, covering five professional fields, namely, geological environment, geologic hazards, groundwater, geological environment of mines and geological relics (geoheritage). Using 1:1 000 000 data sources as the geographic information base, this database is built on 1:500 000 environmental geological surveys in different provinces, county-and city-level geologic hazard surveys, 1:50 000 geologic hazard surveys in key areas, the latest groundwater resources assessment, the second national survey of the geological environment of mines and investigation of such in areas with concentrated mining, and the first survey of geological relics. According to uniform requirements, it integrated the data of hydrological, engineering and environmental geological surveys and monitoring data over the past 20 years as well as the latest related research results. It has a unified system library (symbol, color, pattern and line libraries), with attributes established according to uniform coding rules and requirements, and with maps standardized according to uniform finishing and legend. The database contains 163 professional map layers with a total number of 337 833 elements and a capacity of 8.8 GB. It lays a solid foundation for the dynamic management and updating of maps and the construction of a digital geological environment, and provides detailed fundamental information for the protection and management of China's geological environment, spatial planning of national territory, ecological restoration and the prevention and control of geologic disasters.