A touch display device, a common driving circuit, and a driving method are discussed. The touch display device can include a common driving circuit configured to drive a plurality of common electrodes used for display driving and touch driving, wherein the common driving circuit can include a common signal stabilization amplifier configured to control the average of a first input signal and a second input signal, which are respectively received from a first common electrode and a second common electrode, to correspond to a reference common signal and to output a first control input signal and a second control input signal; and a differential amplifier configured to output a differential sensing signal that is proportional to the difference between the first control input signal and the second control input signal. Accordingly, the impact of display driving and touch driving on each other when simultaneously performing the display driving and the touch driving can be reduced.