Samples of Raney nickel modified by (2R,3R)-(+)-tartaric acid and samples of prepared complexes of tartaric acid with nickel were characterized using atomic absorption spectroscopy (AAS), organic elemental analysis (OEA), thermogravimetric analysis (TGA), X-ray diffractometry (XRD), infra-red spectroscopy (FTIR), spectroscopy in ultraviolet and visible region (UV-VIS-NIR (DRS)), determination of total surface using BET method, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with X-ray microanalyzer (SEM-EDAX). It was found that the content of aluminium in the modified catalysts decreases during the modification due to aluminium leaching to the modifying solution. Simultaneously, increase of the carbon content, which represented an adsorbed amount of tartaric acid, was determined. Furthermore, during modification in the presence of NaBr, its partial adsorption was observed. The total surface area of modified catalysts was lower than in the case of Raney nickel and further decreased in the catalysts modified without NaBr. Using XPS, two kinds of nickel atoms were identified on the surface of modified catalysts, i.e. Ni-0 and Ni2+, while the surface of Raney nickel contained only Ni-0. It was found by XPS analysis that the ratio of Ni2+:Ni-0 was approximately 1:1 on the catalyst surface.