This study aims to develop highly efficient, recyclable solid catalysts for the epoxidation of vegetable oils. An Al 2 O 3-ZrO 2-TiO 2 solid acid catalyst was prepared by a co-precipitation/impregnation method and characterised through scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier-transform infrared and nitrogen adsorption-desorption analyses. The solid acid catalyst with a high surface area and typical slit pore adsorption was successfully synthesised. Al 2 O 3-ZrO 2-TiO 2 also exhibits high stability and improved catalytic efficiency in the epoxidation of soybean oil. An oil conversion rate of 86.6%, which is higher than that of conventional catalysts, was obtained with a catalyst loading of 0.8 wt% and was maintained at 76.6% even after recycling the catalyst three times. The performance of the solid catalyst was slightly superior to that of H 2 SO 4. Therefore, this novel catalyst may potentially be applicable in catalysing soybean oil epoxidation.