Ab initio periodic and cluster Hartree-Fock calculations have been performed to investigate the structural and electronic properties of both V2O5 bulk and (0 0 1) surface. A full bulk geometry optimization yields to good V-O lengths which are found to be in agreement with experiment. The relationship between the bulk and surface structure is investigated by different cluster models with optimized bulk termination. The validity of this approach is discussed through the experimental and theoretical surface results. (C) 2003 Elsevier Science B.V. All rights reserved.