An image display device includes a display panel having a plurality of pixels, and a photoresistor pattern formed in a non-light emitting area between the plurality of pixels; a panel driving controller to drive light-emission control lines of the display panel; and a bio-signal detector that detects an output voltage of the photoresistor pattern which resistance is variable based on light reflected from the target object, and detects a bio-signal of the target object based on the detected output voltage, thereby, detecting the bio-signal of the target object using the image display light from the display panel may allow efficiently detecting the bio-signal without a separate light source or light source operation circuit for detecting the bio-signal.