We prepared durable, uniform, large-area ultrathin transparent films composed of double layers of reduced graphene oxide (RG-O) and multiwalled carbon nanotubes (MWNTs) via a self-assembly process. The adsorption of MWNTs onto RG-O films considerably decreased the sheet resistance of the films without compromising much on transparency. This self-assembly approach could be used to fabricate transparent electronic devices without post-transfer processes on a large scale.