An organic light-emitting display device includes a data line, a scan line, and a display panel including a pixel where the data line crosses the scan line. The pixel includes: a switching transistor including a gate electrode connected to the scan line and a first electrode connected to the data line; a first capacitor between a second electrode of the switching transistor and a reference voltage source; a second capacitor including a first terminal connected to the first electrode of the switching transistor via a first node and a second terminal connected to a second node; a driving transistor including a first electrode connected to a first power source via the second node, a second electrode connected to an organic light-emitting diode, and a gate electrode connected to the reference voltage source via a third node; and a third capacitor between the second and third nodes.