We introduce a novel kind of submicron-sized reduced graphite oxide (μRGO) for the preparation of a transparent conducting film. The special NMP-decorated structure and the small size (∼400 nm) of the μRGO enable us to prepare large-area thin films composed of multiwalled carbon nanotubes (MWNTs) and the functionalized μRGO can fill up the pores of the spiderwork network of the MWNTs partly. This direct assembling composite film possesses a sheet resistance of 152 Ω per square at 84% transmittance.