For exchanging and sharing information and services in e-government, a framework of information service platform (ISP) is presented. The multi-layer architecture of the ISP is introduced They are: users requirement layer, business service layer, business process layer, business function layer and data layer. The lower layers are based on the architecture of web services and the upper layers are related to the institutional and organizational issues. In order to deal with the variation of users requirements and changing environment, the matching and mapping processes with adaptive mechanism are illustrated.