An organic light emitting device includes an electron transport layer including an electron transport material and a metallic compound represented by Formula 1: XaYb  Formula 1: wherein X is an alkaline metal, an alkaline earth metal, or a transition metal, and Y is one of a Group 7 element and an organic group C1-C20, and a is an integer within the range of 1 to 3, and b is an integer within the range of 1 to 3.