An LCD and a touch display panel that can be integrated in the LCD are provided. The touch display panel comprises an active device matrix substrate that includes multiple sensing lines disposed on multiple data lines correspondingly and arranged parallel thereto, and multiple sensing devices formed on multiple scan lines. When an external pressure is exerted, a current is generated in the sensing lines, and the X and Y coordinates of the touch point is determined from a slight leakage current generated in the scan lines. The conventional external touch screen LCD device is substantially improved in response accuracy of the touch coordinates, material costs, and mechanical thickness.