A touch panel display device includes an upper substrate and a lower substrate opposite to the upper substrate. The lower substrate includes scan lines, data lines intersecting with the data lines and contact sensor modules. Each contact sensor module includes a readout line spaced from the data lines, a readout component, and a contact detection module. The readout component includes two ports connected to the readout line and the scan line, respectively; and an equivalent resistance of the readout component is changed according to an electrical field formed between the common electrode and the readout component, such that an output voltage or an output current of the readout line is changed. The contact detection module detects a contact position via a position of the readout line of which the voltage or the current has been changed and a position of the scanned scan line.