Liquid-phase esterification reaction of 1-propanol with pentanoic acid to give propyl pentanoate over Amberlyst 15 has been studied. The reaction carried out in a batch reactor was found to be independent of mass transfer effects in the temperature range of 323.15-363.15K. The reaction is highly temperature sensitive. Increase in 1-propanol concentration has an enhancing effect on the conversion, whereas water acts as an inhibitor. As alcohol-acid mixtures behave nonideally, kinetic analysis has been performed using UNIFAC liquid-phase activities of pentanoic acid, 1-propanol, propyl ester, and water. Observed kinetics is best represented by Eley-Rideal mechanism. Surface reaction was observed to be a rate-limiting step.