The heteropolyacid cobalt salt catalyst immobilized on silyated acid-ctivated palygorskite(PG) was prepared and characterized by infrared spectroscopy. The effects that preparation conditions acted on acetophenone generation were also investigated. Experimental results indicated that the supported CoHPAs heteropolyacid(CoHPAs) cobalt salts (CoHPAs/MPG) exhibited high activity for the reaction, the conversion of ethylbenzene was 72.74 % and the selectivity of acetophenone was 95.42 %. The stability and reusability of the catalyst were investigated and the catalytic activity was retained after recycling 5 times, it has certain use prospects.