Transparent organic light emitting diodes were developed by using a thermally evaporable WO3∕Ag∕WO3 (WAW) as a transparent cathode. A thin Ag layer was introduced as an interlayer between the Li doped electron transport layer and the WAW electrode. A high transparency over 80% was obtained and electron injection was greatly improved by using the thin Ag interlayer between the Li doped layer and the WAW electrode. The driving voltage at 1000cd∕m2 was only 4.5V and the sheet resistance of the WAW electrode was as low as 12Ω∕◻.