Abstract: A series of 12-phosphotungstic acid(PW)and its cesium salt catalysts immobilized on various supports such as ultra-stable Y zeolite (USY), dealuminated USY (DUSY), SiO2 and SBA-15 were prepared. Their specific surface area and acid strength were measured, and their catalytic performance was evaluated in the synthesis of fructone by acetalization of ethyl acetoacetate with ethylene glycol. The high catalytic activity was found over the prepared supported heteropoly compound catalysts in this reaction. However, for the supported PW catalysts, a severe leaching of heteropoly anions into water was observed, leading to their poor reusability. By contrast, the Cs salt of PW catalyst supported on DUSY exhibited very high catalytic activity with high water tolerance and reusability. The conversion of ethyl acetoacetate of 98.7% with the selectivity of fructone above 97% could be obtained over 30%Cs2.5H0.5PW/DUSY under the optimal reaction conditions.