An electroluminescent device, a method for fabricating the same, a display panel, and a display device are disclosed. The electroluminescent device includes a hole inject layer, a hole transport layer, an electron transport layer, and an electron inject layer. At least one of the hole inject layer, the hole transport layer, the electron transport layer, and electron inject layer is a target film including a small molecular layer and a large molecular layer which are arranged in a stacked manner.