The aim of this paper is to investigate synchronization of fractional-order complex dynamic networks. To ensure synchronization of two dynamic networks, an adaptive feedback control method is proposed. With the stability analysis of the fractional-order differential system, we rigorously prove that the controller can make trajectory errors between the drive and response networks synchronized. The simple but practical method can be applied to a class of fractional-order networks without any prior analytical knowledge of the systems. Three illustrative examples are given to show the effectiveness of the proposed method.