Provided are an organic electroluminescent device structure and fabrication method thereof. Surfaces of an anode (20), an organic electroluminescent structure (30) and a cathode (40) of the organic electroluminescent device structure are respectively provided with a wavy structure having periodic undulations, thereby avoiding occurrence of total internal reflection in a process of an emergent light propagating to a substrate, and providing an enhanced light extraction efficiency. A PEDOT:PSS film is used as an anode material replacing an ITO material, thereby reducing costs. The fabrication method of the organic electroluminescent device adopts a wet coating process to form a PEDOT:PSS film serving as an anode of the organic electroluminescent device, thereby reducing production costs. In addition, the PEDOT:PSS film is patterned by transfer printing to form a wavy structure having periodic undulations on the PEDOT:PSS film, namely on the anode, thereby avoiding occurrence of total internal reflection within the organic electroluminescent device. Thus, most light can be propagated out through the substrate, thereby effectively improving a light extraction efficiency of a bottom-emission organic electroluminescent device.