In this article, an angle-resolved photoelectron spectroscopy (ARPES), X-ray absorption spectroscopy (XAS), and density-functional theory (DFT) investigations of water and ammonia adsorption on graphene/Ni(111) are presented. The results of adsorption on graphene/Ni(111) obtained in this study reveal the existence of interface states, originating from the strong hybridization of the graphene π and spin-polarized Ni 3d valence band states. ARPES and XAS data of the H2O (NH3)/graphene/Ni(111) system give an information regarding the kind of interaction between the adsorbed molecules and the graphene on Ni(111). The presented experimental data are compared with the results obtained in the framework of the DFT approach.