An image scanner of the present invention includes a document feeder, a first scanning section, a start reception section, and a single mode execution section. The document feeder is configured to feed a sheet of document. The first scanning section is configured to scan an image on the document during movement of the document. The start reception section is configured to receive an instruction to start scanning the image on the document from a user. The single mode execution section is configured to execute a single mode to cause the document feeder and the first scanning section to perform scanning of an image on the document every time the start reception section receives the start instruction.