Different types of thin film transistors are disposed on the same flexible substrate and an organic light emitting display using the same includes a display area and a non-display area; a first buffer layer over an entire surface of the flexible substrate; a driving transistor on the buffer layer in the display area, the driving transistor including a polycrystalline silicon (LTPS) layer, a first gate electrode, a first source electrode, and a first drain electrode; a capacitor electrode on the first source electrode of the driving transistor and forming a storage capacitor together with the first source electrode; a switching transistor in the display area to be spaced apart from the driving transistor; and a dummy electrode on the switching transistor, the dummy electrode formed of the same material as the capacitor electrode, and disposed on the same plane as the capacitor.