Abstract: Basing on GIS, multimedia, distributed network and modeling technologies, the Decision Support System for Water-Saving Agriculture in China was researched and developed successfully. The system offered many functions, such as data input, information storage, data query, statistical analysis and decision support. Applying more modern technologies in the water-saving agriculture for project management, investment decision-making, and water-saving technologies consultation was the main purpose of system development. The article expounded the design idea and the key technologies. Using ComGIS to integrate with database to display the graphic function was also introduced in detail.