A coordinate input apparatus has an effective area in a vibration transmission member for inputting a vibration from a vibration generator and a computing unit that computes the coordinates of the position of the vibration generator on the basis of the delay time between the vibration generation and the detection of the vibrations by a vibration sensor. A vibration proof material is disposed in the periphery of the vibration transmission member to prevent the inputted vibrations from being reflected at the acoustic impedance boundary of the vibration transmission member. The vibration proof material is disposed so that the spacing between the edge of the effective area and the edge of the vibration proof material facing the effective area edge becomes larger with increasing distance along the effective area edge from the vibration sensor.