It has been shown that the activated carbon-supported zirconium sulfate (ZS) is an efficient solid catalyst for the esterification of oleic acid by n-butanol under solvent-free condition. The effect of mole ratio of the reactant, time and catalyst loading on the conversion was examined. The correlation among XRD, nitrogen adsorption data and catalytic activity suggested that ZS has been finely dispersed on activated carbon, which are active in the esterification of oleic acid. The reaction shows that the supported ZS exhibits a higher activity than that of parent ZS and conventional resins.