The invention provides an organic electroluminescent device comprising an anode conductive substrate, a functional layer, a luminescent layer, a cathode layer, a protective layer, and an encapsulating layer. The encapsulating layer comprises an insulating layer, metallic layers, and plate glass. The insulating layer is arranged in a surrounding manner along the edge of the top surface of the anode conductive substrate. A groove is surrounded by the insulating layer surrounding structure. The functional layer, the luminescent layer, the cathode layer, and the protective layer are successively extended from the top surface of the anode conductive substrate to the groove. The metallic layers are disposed on the top surface of the insulating layer and a gap is arranged between the metallic layers and the functional layer, the luminescent layer, the cathode layer, and the protective layer. The sum of heights of the insulating layer and the metallic layers is more than that of the functional layer, the luminescent layer, the cathode layer, and the protective layer. The plate glass is disposed on the top surfaces of the metallic layers. The invention also provides a method for producing the organic electroluminescent device. The method effectively reduces erosion, caused by moisture and oxygen, on the device, and substantially prolongs the service life of the device.