GML　expresses　geographic　information　in　text,　and　it　provides　an　extensible　and　standard　way　of　spatial　information　encoding.　At　the　present　time,　the　management　of　GML　data　is　in　terms　of　document.　By　this　way,　the　inquiry　and　update　of　GML　data　is　inefficient,　and　it　demands　high　memory　when　the　document　is　comparatively　large.　In　this　respect,　the　paper　put　forward　a　data　management　of　GML　based　on　PostgreSQL.　It　designs　four　kinds　of　inquiries,　which　are　inquiry　of　metadata,　inquiry　of　geometry　based　on　property,　inquiry　of　property　based　on　spatial　information,　and　inquiry　of　spatial　data　based　on　location.　At　the　same　time,　it　designs　and　implements　the　visualization　of　the　inquired　WKT　data.　©　2008　SPIE.