An efficient synthesis of bis(indolyl)methanes from aldehydes with indoles through graphene oxide-catalyzed Friedel-Crafts alkylation is developed. The reaction proceeds in water by using graphene oxide as the single catalyst to provide the desired products in good to excellent yields. Also, this methodology has a broad substrate scope, and is environment friendly and cost economic. (C) 2016 Published by Elsevier B.V.