The present invention provides a catalytic activity accelerant. The accelerant is added to stock oil for increasing the catalyst activity, the depth of catalytic hydrogenation and the yield of catalytic hydrogenation product, degrading the reaction conditions of catalytic hydrogenation, and improving the quality of product. The catalytic activity accelerant is consisted of an alkyl succinimide derivative, an alkyl phenol and a surfactant. The amount of the alkyl succinimide derivative in the accelerant is 5-70 wt. %. The amount of the alkyl phenol in the accelerant is 2-70 wt. %. The amount of the surfactant in the accelerant is 2-70 wt. %.