An image reading apparatus for reading an image includes a light receiving element that receives light from the image so as to perform photoelectric conversion, an amplifier which is electrically connected to the light receiving element, and amplifies a signal generated by photoelectric conversion, a switch element which is electrically connected to both ends of the amplifier so as to be parallel to the amplifier, a first capacitance which are electrically connected to both ends of the amplifier so as to be parallel to the amplifier, and a second capacitance which has one end which is electrically connected to one end of the light receiving element and one end of the amplifier. A second signal of which potential is changed after potential of a first signal input to a control terminal of the switch element is changed is applied to another end of the second capacitance.