To meet the need that real-time access to scientific fertilizer suggestions, and make full use of existing digital resources of cultivated land, a solution is proposed based on WebGIS and fertilization model. With Jinshan county of Hubei province as a case, under the support of spatial database of cultivated land resource, the prescription fertilization system is developed based on MapXtreme and target yield model. It provides intuitive and convenient services on scientific fertilization. It is also good to improve the utilization rate of fertilizer and reduce investment to achieve greater economic benefits.