Disclosed is a light-emitting device using a transistor structure, including a substrate, a first gate electrode, a first insulating layer, a source electrode, a drain electrode, and a light-emitting layer formed between the source electrode and the drain electrode in a direction parallel to these electrodes. In the light-emitting device using the transistor structure, it is possible to adjust the mobility of electrons or holes and to selectively set a light-emitting region through the control of the magnitude of voltage applied to the gate electrode, thus increasing the lifespan of the light-emitting device, facilitating the manufacturing process thereof, and realizing light-emitting or light-receiving properties having high efficiency and high purity.