Grid technology is receiving an increasing attention in the domain of data mining and knowledge discovery. Knowledge Grid is a platform that enables uniform and effective data mining and knowledge discovery, sharing and management across the Internet. This paper presents a Grid based spatial knowledge discovery environment named Spatial Knowledge Grid. Based-on this platform, we study the produce of spatial knowledge discovery in the grid environment, design an architecture for integrated spatial knowledge application in grid environment, and the advanced technologies employed to achieve spatial knowledge discovery and sharing in our work are also gone into details in this paper.