A touch input device capable of detecting a pressure of a touch on a touch surface may be provided that includes: a display module; and a pressure sensor which is disposed at a position where a distance between the pressure sensor and a reference potential layer is changeable according to the touch on the touch surface. The distance is changeable according to a pressure magnitude of the touch. The pressure sensor outputs a signal including information on a capacitance which is changed according to the distance. The pressure sensor includes a plurality of electrodes to form a plurality of channels. The pressure magnitude of the touch is detected on the basis of a change amount of the capacitance detected in each of the channels. According to the embodiment of the present invention, it is possible to provide a pressure sensor for pressure detection, a touch input device including the same, and a pressure detection method using the same. In addition, according to the embodiment of the present invention, it is possible to provide the pressure sensor having a high-pressure detection accuracy of the touch and the touch input device including the pressure sensor.