Three Br鰊sted acidic ionic liquids including 1-methyl-3-(3-sulfopropyl)imidazolium hydrogen sulfate([SO3H-pmim]HSO4), 1-(3-sulfopropyl)pyridinium hydrogen sulfate([SO3H-ppy]HSO4) and N-(3-sulfopropyl)triethylammonium hydrogen sulfate([SO3H-ptea]HSO4) were synthesized. A one-pot reaction of o-aminoacetophenone and aromatic aldehydes in the presence of ionic liquid as an effective catalyst for the synthesis of 2-aryl-2,3-dihydro-4(1H)-quinolones was described. The activity and reusability of ionic liquid as catalyst for reaction of o-aminoacetophenone and aromatic aldehydes were investigated. The ionic liquids exhibited high catalytic activity and good reusability for reaction of o-aminoacetophenone and aromatic aldehydes, and the catalytic performance of [SO3H-ptea]HSO4 could be much better than that of others. The reaction of o-aminoacetophenone and aromatic aldehydes catalyzed by [SO3H-ptea]HSO4 could proceed well to desired product in 68.3%～95.1% yields under the conditions of solvent-free and reaction temperature 60 ℃. The ionic liquid was reused at least five times without significant decrease in activity after drying under vacuum.