An OLED display includes a first polysilicon layer pattern on a substrate having a first gate electrode, a second gate electrode, and a first capacitor electrode, a gate insulating layer pattern, a second polysilicon layer pattern including a first active layer, a second active layer, and a capacitor polycrystalline dummy layer, a third amorphous silicon layer pattern including first source and drain resistant contact layers on a predetermined region of the first active layer, second source and drain resistant contact layers on a predetermined region of the second active layer, and a capacitor amorphous dummy layer on the capacitor polycrystalline dummy layer, and a data metal layer pattern including first source/drain electrodes, second source/drain electrodes, and a second capacitor electrode.