We report highly transparent and low resistive new cathode structures, which basically consist of nano-composite layer/Ag/WO3 for transparent organic light-emitting diode (TOLED) applications. Our new cathode structure exhibits an extremely high transmittance of 91.2% at 550 nm, a low sheet resistance of 5.4 Ω □(-1), and excellent electron injection properties. Such a high transmittance along with a low resistivity of the fabricated new cathode could be explained by surface-modifying behavior with the generation of a nano-composite thin silver oxide layer during Ag deposition. Chemical interaction at the interface between the electron injection layer and the electron transport layer results in good electron injection properties in TOLEDs. The fabricated TOLEDs with our new cathode structures have a full device transmittance of 85-87% at 550 nm.