The esterification of several cyclic olefins with saturated and unsaturated carboxylic acids has been studied over highly dispersed strongly acidic ion-exchange resins based on Nafion, where the Nafion is entrapped within a porous silica matrix. Over these new catalysts the accessibility of the acid sites is much improved, in comparison to the original material. The activity has been compared to that of Amberlyst 15. The Nafion-based catalyst materials are superior to the weaker acidity Amberlyst catalysts when less active olefins are used and especially at low temperatures.