The Web 2.0 maximizes the Internet concept of encouraging its users to cooperate effectively for the offer of virtual services and content organization. Among the various potentialities of the Web 2.0, folksonomy appears as a result of the free assignment of tags to the Web’s resources by their users/ readers. Despite tags describe the Web’s resources, generally they are not integrated in the metadata. In order for them to be intelligible by machines and therefore used in the Semantic Web context, they have to be automatically allocated to specific metadata elements. There are many metadata formats. The focus of this investigation will be the Dublin Core Metadata Terms (DCTerms) that is a widely used set of properties for the description of electronic resources. A subset of DCTerms, the Dublin Core Metadata Element Set (DCMES), has been adopted by the majority of Institutional Repositories’ platforms as a way to promote interoperability. We propose a research that intends to identify elements of the metadata originated from folksonomies and propose an application profile for DC Social Tagging. That will allow tags to be conveniently processed by interoperability protocols, particularly the Open Archives Initiative – Protocol for Metadata Harvesting (OAI-PMH). This paper will present the results of the pilot study developed in the beginning of the research as well as the metadata elements preliminarily defined.