In this study, we prepared flexible and transparent hybrid electrodes based on an aqueous solution of non-oxidized graphene and single-walled carbon nanotubes. We used a simple halogen intercalation method to obtain high-quality graphene flakes without a redox process and prepared hybrid films using aqueous solutions of graphene, single-walled carbon nanotubes, and sodium dodecyl sulfate surfactant. The hybrid films showed excellent electrode properties, such as an optical transmittance of >= 90%, a sheet resistance of similar to 3.5 k Omega/sq., a flexibility of up to epsilon = 3.6% ((R) = 1.4 mm), and a high mechanical stability, even after 10(3) bending cycles at epsilon = 2.0% ((R) = 2.5 mm). Using the hybrid electrodes, thin-film transistors (TFTs) were fabricated, which exhibited an electron mobility of similar to 6.7 cm(2) V-1 s(-1), a current on-off ratio of similar to 1.04 x 10(7), and a subthreshold voltage of similar to 0.122 V/decade. These electrical properties are comparable with those of TFTs fabricated using Al electrodes. This suggests the possibility of customizing flexible transparent electrodes within a carbon nanomaterial system.