The density functional LCAO calculations using DFT (PBE) and hybrid HF-DFT (B3LYP) functional are presented for the electronic and structural properties of bare and hydroxylated low index surfaces of SnO₂ crystal. The dissociative and associative water adsorption on (110) and (100) SnO₂ surfaces is investigated. The role of geometrical and chemical-bonding factors in the relative stability of different adsorption structures is discussed. The comparison of plain DFT functionals with the B3LYP hybrid functional shows that, in contrast to former DFT plane-wave calculations (spontaneous dissociation), an associative adsorption of the water molecules becomes possible not only in the case of the (100) surface but also at the most stable (110) surface.