A method for making an organic light emitting diode includes providing a first carbon nanotube composite structure having a first surface and a second surface opposite to the first surface. The first carbon nanotube composite structure includes a polymer and a plurality of first carbon nanotubes dispersed in the polymer. A preform structure includes a support body, an anode electrode, a hole transport layer, and an organic light emitting layer stacked on each other in that order. The preform structure is located on the first surface, wherein the first surface is in direct contact with the organic light emitting layer. A cathode electrode is formed on the second surface.