An input device mounted in a vehicle, separated from a display unit and configured to input a finger operation to an operation surface to operate an image of the display unit is provided. The input device includes a detector that detects presence and absence of a finger in a groove, and controller that prohibits an input of a finger operation to an operation surface when a finger operation to the operation surface has not been performed for a predetermined time or longer and that cancels the prohibition of the input when determining the presence of sliding of the finger in the groove based on detection of the finger in the groove by the detector.