Exploring a method of developing application system which can access and manipulate a mass of spatial data effectively under integration storage mode of GIS data in Oracle Spatial, is the research hot spot. This paper defines more compact, robust and reliable class modules for accessing spatial data, carries on the visualization processing of spatial data using MapX, and gives a method for enhancing the ability to manipulate spatial data in GIS system through using OCCI to call spatial operators in Oracle Spatial, which unites advantages of OCCI, MapX and Spatial to develop GIS application system fully.