A thin film transistor array substrate includes: a driving thin film transistor including an active layer having a bent shape, where the active layer includes: a first active pattern extending substantially in a first direction; and a second active pattern extending substantially in a second direction perpendicular to the first direction and connected to the first active pattern, and a gate electrode disposed on the active layer, where gate electrode overlaps the first active pattern and exposes the second active pattern; and a capacitor including a first electrode defined by the gate electrode of the driving thin film transistor, and a second electrode disposed on the first electrode, where the second electrode overlaps substantially an entire surface of the first electrode.