Institutional Repositories (IR) disseminates rich source of digitized material drafted and published by scholars. Many of the research institutions and universities across the world are facilitating open access (OA) to their intellectual outputs through their respective OAIR (Open access Institutional Repositories. Open Archive Initiative (OAI) based service provider harvest metadata from register OAI – compliant systems and build a central index on the harvested metadata .This central index serves as a discovery tool for end users, who need not be aware of the existence of distributed repositories. One such OAI based service provider is Directory of Open Access Repositories (DOAR). It is a union catalog of IR which gives access to OAIR in the world. This study has made an attempt to overview IR available on DOAR. DOAR is a metadata harvesting service provider which provides access to open access repositories in the world.