Jnsymmetrical arylbis(3-indolyl)methanes have been synthesized via a Bronsted acid catalyzed Friedel-Crafts alkylation of α-(3-indolyl)benzylamines with N-methylindole. With 5 mol% of the catalyst, the reaction proceeds smoothly under mild conditions, affording the unsymmetrical triarylmethanes in excellent yields (up to 98%).