Method of detecting a touched position on a touch display of a display apparatus includes determining an amount of an electrical charge generated by a touch on the touch display panel of a display apparatus, determining a difference between the amount of the electrical charge generated from the touch and an amount of a reference electrical charge and comparing this difference to a threshold value, detecting the position of the touch if it is determined that the difference between the amount of the electrical charge generated from the touch and the amount of the reference electrical charge is substantially the same as or larger than the threshold value and detecting the touched position using a pressure according to the touch if it is determined that difference between the amount of the electrical charge and the amount of the reference voltage is smaller than the threshold value.