According to one embodiment of the present invention, provided is an input device for a computer, characterized by comprising: a button movable by an external force; an elastic part which is positioned under the button, is deformed or compressed by movement of the button, and provides an elastic force in response to the movement of the button; and a switch which is turned on or off by the movement of the button, wherein the button is capable of moving along an "on" section, which is a section from the uppermost position to a position where the switch is turned on, and an extra section which is a section up to a position lower than the "on" section.