Provided is a method of integrating an organic light emitting diode (OLED) and an organic field effect transistor (OFET) including: preparing an organic field effect transistor including at least one first electrode and an organic semiconductor on a first substrate; preparing an organic light emitting diode including at least one second electrode and an organic emission layer on a second substrate; disposing the OFET and the OLED to make the first and second electrodes opposite to each other; inserting an insulating layer, to which a predetermined metal contact line for electrically connecting the first and second electrodes is securely fixed, between the OFET and the OLED; and adhering the OFET and the OLED to integrate them as one device, whereby it is possible to effectively perform active driving, to extend a lifetime due to a high aperture ratio, and to produce the device using a simple process at a low cost.