The invention provides an active matrix organic light emitting display device and method of fabricating the same in which at least one of a data line and a power supply line of a unit pixel is designed to pass over at least one of a source region, a channel region, or a drain region in the corresponding semiconductor layer, except for in an area corresponding to a contact hole, so that an aperture ratio and a pixel size of the active matrix organic light emitting display device are enhanced. This arrangement of components creates areas of free space that may be used to accommodate additional thin film transistors and/or other circuit components that improve the screen resolution. This arrangement may also increase the aperture ratio and the size of the pixel of the active matrix organic light emitting display device without adding and modifying existing fabrication processes.