An organic electroluminescent display device includes a gate line on a first substrate; a data line intersecting the gate line on the first substrate; a switching thin film transistor at the intersection of the gate line and data line; a driving thin film transistor having a first driving dual gate, a driving active layer, a driving source, a driving drain, and a second driving dual gate, and the driving thin film transistor connected to the switching thin film transistor; an organic electroluminescent diode on a second substrate; and a connection pattern connecting the driving drain and the organic electroluminescent diode between the first and second substrates.