The　service　matching　algorithm　is　key　to　service　discovery.　In　this　paper,　according　to　the　four-level　matching　algorithm,　the　geospatial　services　discovery　algorithm　is　also　designed,　which　uses　hierarchy　matching,　and　uses　ontology　classification　tree　in　I/O　matching　to　converse　the　ontology　similarities　into　the　distance　between　nodes.　It　is　proved　that　the　new　algorithm　not　only　differentiates　the　geospatial　services　matching　level,　but　also　differentiates　the　similarities　between　the　identical　matching　level,　and　can　meet　the　geospatial　services　discovery　well.　©　2010　IEEE.