An image reading apparatus includes a solid-state image sensor having a pixel array section in which pixels each including a photoelectric transducer are arrayed, a charge transfer register that transfers a signal charge transferred from each of the pixels of the pixel array section, and an output section that converts the signal charge transferred by the charge transfer register into an electrical signal and outputs the electrical signal; a driving unit that drives the charge transfer register according to a first timing signal, and the output section according to a second timing signal; and a power supplying unit that supplies power of different power systems to a circuit portion handling the first timing signal and a circuit portion handling the second timing signal of the driving unit.