The oxygen electrode is the most important part in lithium air batteries for oxygen reduction and evolution reaction (ORR/OER) in order to get closer to the theoretical energy density of 11,238 Wh/kg, which is the best among the batteries ever developed. Many carbon materials have been researched as a candidate oxygen electrode for lithium air batteries such as a carbon black, CNTs and 2D graphene. Compared to the many research results, there are still many controversies on optimum oxygen electrode for lithium air batteries. The most important properties for oxygen electrode are the microstructures such as an optimum pore size of less than 10 nm and pore size distributions which affect greatly to ORR/OER at the interface of between the electrode and electrolyte.
 In this perspective, the hydrothermally self-assembled 3D RGO has great potential as an oxygen electrode. Because, it has a wide range of pore size and large surface area, as well as a high conductive network. However, 3D RGO has some obstacle to be surpassed such as side reactions which induce a large voltage gap, and decay the cycling performances. If the electrochemical reaction mechanisms of 3D RGO in lithium air batteries are well investigated clearly, the 3D RGO is a still desirable electrode for lithium air batteries. In this research, we synthesized self-assembled 3D RGO electrode by means of hydrothermal methods. The electrochemical properties and reaction mechanisms of the self assembled 3D RGO electrode were investigated using BET, EIS, SEM, XRD. As a result, we carefully assessed the possibility of 3D RGO as a game changer in lithium air batteries.