Comparing the catalysts’ performance of palladium on carbon applied in the catalytic hydrogenation synthesis of indoxacarb intermediate, the effects of the carriers of catalysts and pretreatment were investigated in this paper. The results showed that nitric acid reflux treatment with ultrasound can effectively remove the ash of activated carbon and reduce the impact of those impurities on properties of catalysts. And in the catalytic reaction of indoxacarb intermediate, the Pd/C catalyst on activated carbon with large average pore size and high specific surface area exhibited better catalytic reactivity and selectivity.