A touch input device includes a first sensor having a first surface to which a touch is input, and a second surface opposing the first surface, and a second sensor connected to the second surface of the first sensor, and spaced apart from the first sensor in a vertical direction, wherein the first sensor measures a first position of the touch input to the first surface, wherein the second sensor measures a force caused by the touch input to the first surface of the first sensor, and calculates a second position by applying the force measured by the second sensor to force and moment equilibrium equations, when a distance between the first position and the second position is greater than or less than a threshold, the touch input to the first surface of the first sensor is determined to be a shear force or a sliding gesture, respectively.