A display device include a first surface, a sensing capacitor having a sensing input electrode and a sensing output electrode, wherein the sensing capacitor stores a first amount of charges and the sensing capacitor stored a second amount of charges when an external object contacts on the first surface, a sensing input signal line electrically connected with the sensing input electrode and receiving a sensing input signal to charge the sensing capacitor to the first amount of charges, a sensing output signal line electrically connected with the sensing output electrode, and a sensing signal processor connected with the sensing output signal line, wherein the sensing signal processor determines whether an external objects contact on the first surface based on a voltage difference between the first amount of charges and the second amount of charges stored in the sensing capacitor.