Virtual Enterprise enables companies to collaborate through sharing of resources, and therefore allows them to enjoy the benefits of virtual integration. The essence of Virtual Enterprise implementation on the Web lies in data integration. This paper describes key research issues in implementation of data integration in virtual enterprise using semantic web service. The architectural framework of the proposed data integration infrastructure adopts a mediated ontology approach to data integration in which each data source is described by its own ontology and translations between different ontologies are by means of mediation. We also propose to use the concept of an active data warehousing system for virtual enterprise data aggregation. The paper briefly describes the preliminary study for the project proposal.