GeoPortal Systems are being considered one of the most important object in interoperability concept for Spatial data Management. With the developing technology of the information age, the need for accessing to spatial data is caused to effort for establishing national, regional and local information systems by institutes and organizations. Sharing and accessing of spatial datasets between institutes and organizations are being more important within interoperability concept.In this study, Open Access GeoPortal System is designed and applied to establish a common platform for institutes/organizations to analyze, interact, view, query and share spatial data. Open Access GeoPortal System, which is aimed to develop effective solutions in the field of using and sharing spatial data and establish interoperability concept, intends to provide an infrastructure for users to realize functions related with spatial data on web without installing any software. Open Access GeoPortal System is providing standardization stage acceleration, interoperability concept establishment and solutions to problems of spatial data thanks to the developed functions and processes which are working on international standardization organizations as like INSPIRE, ISO, W3C and OGC.