Semantic web offers new opportunities to multi-sources integration field, and many approaches like P2P systems are revisited taking into account the new requirements. In this chapter, the authors present their P2P heterogeneous and distributed data integration system. It is a super-peer system, where peers are regrouped by type of data (relational, image, text, etc.) around a super-peer which contains a domain ontology. Peers data sources are exported in a common format in the form of a semantically rich ontology. Schemas reconciliation is done by matching domain and local ontologies by the use of a similarity function whose contribution is based on the direct and indirect semantic neighborhood. Queries are described using ontologies, then routed towards relevant peers thanks to a semantic topology built on top of the existing physical one.