A communication interface that can decrease a transmission time between a touch driving circuit and a touch controller at the time of performing a pen touch sensing operation is provided. The touch display device can include a touch panel in which touch electrodes are arranged; a touch controller that outputs a first master signal to a first master pin corresponding to one end of a first interface, outputs a second master signal to a second master pin corresponding to one end of a second interface, receives first slave data from the first master pin, and receives second slave data from the second master pin; and a touch driving circuit that receives the first and second master signals, and outputs the first slave data to a first slave pin and outputs the second slave data to a second slave pin in response to the first master signal and the second master signal.