Abstract: In information grid information sharing is very important for the grid units to cooperate with each other and to react to the ever changing environment From the point of view of resolving semantic heterogeneity, an ontology based global view construction approach is proposed to achieve information sharing in information grid In this approach, the local ontologies are merged into the global ontology by means of similarity relations As the global ontology, the global view is constructed through integrating the local information source schemas An example of constructing the global views in the E government information grid is presented to illustrate the approach Finally, the related work is introduced, and the conclusion and future work are given