simple, efficient and ecofriendly method for one pot synthesis of 2-arylbenzimidazoles has been developed in acetonitrile using ultrasound and amberlite IR-120 resin at room temperature. Experimental results showed that ultrasound induced amberlite IR-120 resin efficiently synthesized substituted 2-arylbenzimidazoles (96 – 68 %) and recyclable up to five times without loss of activity. The method provides several advantages such as green solvent, simple work-up procedure, shorter reaction time and higher yield.