An organic light-emitting diode (OLED) display device using hybrid type thin-film transistors (TFTs) is disclosed. The OLED display device includes an etch stopper film on a semiconductor pattern to prevent over etching of the semiconductor pattern located on a lower position and source and drain electrodes are brought in direct contact with the semiconductor pattern while passing through the etch stopper film to prevent malfunction of the TFTs due to surface resistance due to the etch stopper film. Thus, characteristics of the TFTs and process stability are secured.