According to the present invention, an electro-optic device comprises: a substrate which is split into a light emitting unit and a non-light emitting unit, wherein said light emitting unit is divided into a plurality of driving regions; an electrode pad which is formed in the non-light emitting unit of the substrate; and an electrode unit which comprises a plurality of supplementary electrodes each of which has one end connected to the electrode pad and has the other end connected to the centers of each of the plurality of driving regions, and transparent electrodes formed on the upper sides of the plurality of supplementary electrodes in the light emitting unit, wherein the area of each of the plurality of driving regions is set to an area in which no voltage drop occurs, and the plurality of supplementary electrodes are manufactured in the same length. Thus, according to the present invention, if power is supplied to each one end of the plurality of supplementary electrodes by using the electrode pad, the power is transmitted, at the same time, to the other ends of each of the plurality of supplementary electrodes. Therefore, the power is simultaneously supplied to each center of the plurality of driving regions regardless of the distance between the electrode pad and the driving regions. Further, as mentioned above, a voltage drop phenomenon is prevented since the light emitting unit is divided into the plurality of driving regions in which no voltage drop occurs. That is to say, uniform currents can flow on the front side of each driving region irrespective of the distance between the supplementary electrodes and the driving regions. Consequently, a large-scaled organic light emitting device which can show uniform brightness properties in the overall light emitting unit can be manufactured.