A series of ZrO2-modified Fe/SiO2 catalysts with the same composition were prepared by different methods. These solids were characterized by N-2 adsorption, Fourier transform infrared spectroscopy, temperature-programmed reduction, temperature-programmed desorption, transmission electronic microscopy and Mossbauer spectroscopy. The results indicated that the modification of Fe-SiO2 interaction was strongly depended on the method of preparation. It was found that the strong Fe-SiO2 interaction could be effectively weakened if Zr species and SiO2 were pre-precipitated (Zr-2-B and Zr-2-C catalysts), even though the ZrO2 level was low. Consequently, the reduction and carburization ability of the catalyst was enhanced and the Fischer-Tropsch synthesis activity was increased eventually. The products selectivity variation trend indicated that the selectivity to gaseous and light hydrocarbons was increased, whereas that to heavy hydrocarbons and olefin was suppressed when the Zr species and SiO2 were precipitated before the precipitation of Fe3+ cation. (C) 2011 Published by Elsevier B.V.