The geometries, magnetic behaviors and electronic structures of single transition-metal (V, Cr, Mn, Fe, Co and Ni) adsorbed BN sheet have been investigated within the framework of the density functional theory. We find that the stable adsorption configuration and adsorption type depend on the choice of the exchange-correlation functional (GGA or LDA), which derives from the over-binding shortcoming of LDA. When supported on BN sheet, the spin polarization for V, Cr, Mn, Fe and Co adsorbed systems reaches 100% at the Fermi level or HOMO level, which can be used as potential spin-filtering material in spintronics. (c) 2012 Elsevier B.V. All rights reserved.