Abstract: To realize wheat quality monitoring and planting optimization in fertilization and irrigation, a web-based geographical information system was developed. On the basis of agronomic knowledge for wheat planting, it determined the main factors which determine the formation of wheat grain quality, including wheat variety, soil texture, wheat growing status, blight temperature of wheat canopy, surface soil moisture. The multi-factors evaluation model for estimating wheat grain quality based on the multiple factors that derived from remotely sensed images or background data stored in GIS was developed. Finally, the distribution of integrative quality index or quality grades indicating the grain quality was obtained. Supported by Component GIS, Web-based GIS, Spatial Database Engine technology (SDE) and other advanced Geographical Information Technologies, the system well dealt with the fusion analysis of remotely-sensed data, GIS data and other multi-sources data, flexible management of models and knowledge, and effective linkage between Remote Sensing retrieval models and agronomic models was built.