Based on ab initio theory, we theoretically investigated the interfacial spin polarization by adsorbing a benzene-dithiolate molecule onto a nickel surface with different interfacial angles. A variable magnitude and even an inversion of the interfacial spin polarization are observed with the increase of the interfacial angle. The orbital analysis shows that the interfacial spin polarization is codetermined by two kinds of orbital hybridization between the molecule and the ferromagnet, the p(z)-d hybridization and the sp(3)-d hybridization, which show different dependence on the angle. These results indicate a new way to manipulate the spin polarization at organic spinterface. (C) 2016 Elsevier B.V. All rights reserved.