The promotional effects of ZrO2 on Ni/ZrO2-SiO2 catalysts were investigated by the comparison of Ni/SiO2 and Ni/ZrO2-SiO2 activity in the hydrogenation of maleic anhydride (MA) to gamma-butyrolactone (GBL), and by the measurements of X-ray diffraction (XRD), Fourier transform infrared (FT-IR), temperature-programmed reduction (TPR) and ammonia temperature-programmed desorption (NH3-TPD). The presence of ZrO2 led to an obvious increase of GBL yield. The promotion effect could be attributed to the possible presence of Zr4+ species on the catalyst surface owing to the higher ionicity of the Zr-O bonds, and to the proper interaction of Ni with the ZrO2-SiO2 support that is regulated by the presence of ZrO2.