An object-oriented data model for the finite element method is described in this paper. In the data model, which is based on the Entity-Relationship model, a finite element is treated as an object. The proposed data model is applied to the h -version adaptive mesh technique. In the h -version adaptive mesh technique, an element is divided into 2 or 4 elements recursively to reduce the error norm for the whole analysis domain. The present mesh refinement system is constructed using the C+ + object-oriented programming language for the implimentation of the data model. To verify the mesh refinement system, we have chosen some 2-dimensional stress concentration and singularity problems. The results show that the newly proposed data model is very useful for the h -version adaptive mesh technique. Moreover, the data model shows great promise for the integrated FEM systems.