The present disclosure provides a light-emitting device, a pixel unit, a method for manufacturing the pixel unit, and a display device. The light-emitting device comprises a first electrode, an organic light-emitting layer and a second electrode which are sequentially disposed on a substrate; the first electrode comprises a reflecting layer, a transparent insulating layer and a transparent contact layer which are sequentially disposed on the substrate; and the second electrode is a semi-transparent electrode, so that a cavity is formed between the second electrode and the reflecting layer.