PRINTER

A printer includes: a pattern printing unit (41) that forms a first mark on a first side of a document and forms a second mark (61a, 61b, 61c) on a second side of the document; a glass platen (12) for placing the document including the first mark and the second mark (61a, 61b, 61c) formed by the pattern printing unit (41); a main body (11) including a third mark (13) depicted in at least one portion of an area surrounding the glass platen (12); a scanner function unit (30) that reads the first mark formed on the first side of the document placed on the glass platen (12); and an adjusting unit (42) that adjusts a printing position based on a result obtained by reading the first mark. The second mark (61a, 61b, 61c) is positioned opposite to the third mark (13) when the first mark is read by the scanner function unit (30).