An organic light emitting display device including pixels positioned in regions defined by scan lines and light emission control lines extending in a first direction, and data lines extending in a second direction different from the first direction, the pixels being configured to control an amount of current flowing from a first power source to a second power source by way of organic light emitting diodes (OLEDs) in response to data signals, organic light emitting display device includes a scan driver configured to sequentially supply scan signals to the scan lines and light emission control signals to the light emission control lines during an inspection period, and a data driver configured to supply inspection data signals to the data lines in synchronization with the scan signals during the inspection period.