An organic luminescence device including an electron transport layer, which comprises an electron transporting material and a metal oxide represented by Formula 1: AaOb. In Formula 1: A is Li, Mo, Ba, B, or Cs; a is a number in the range of 1 to 3; and b is a number in the range of 1 to 3. The electron transporting material reduces an electron injection barrier and the resistance at the interface between an EML and an ETL, resulting in an increase in the lifespan of the organic luminescence device. The numbers of holes and electrons injected to the EML are balanced, and driving characteristics of the organic luminescence device are improved.