In this paper, ten kinds of 5-[(Indol-3-yl)-arylmethyl]-2,2-pentamethylene -1,3-dioxane-4,6-dione derivatives （3-indole derivatives）were synthesized by the three component condensation reactions of indole with aromatic aldehydes and 2,2-pentamethylene -1,3-dioxane-4,6-dione using succinimide-N-sulfonic acid lanthanum as catalyst, without solvent under ultrasonic irradiation. The results indicate that the yield ranged from 82.4% to 98.5%，when using 3%( the mole fraction of indole) succinimide-N-sulfonic acid lanthanum and reacting at 30℃ for 20-60min. In addition, the possible catalytic mechanism for the reaction catalyzed by succinimide-N-sulfonic acid lanthanum was proposed. The advantages of this protocol were mild reacions conditions, short reaction time, wide substrate scope, excellent yields and benign to environment, Furthermore, the catalyst could be recovered four times conveniently and reused efficiently.