To provide an image reader having a holding member structure which eliminates abnormal images by original guide members, can surely hold down a document to a platen glass, reduces the attraction force between a hold-down sheet and the platen glass and improves the operability of a holding member.

The image reader for reading the image of the document 8 by pressing the document 8 to the platen glass 1 for reading has the hold down sheet 4 for pressing the document 8 to the platen glass 1 and the holding member 5 for holding the hold-down sheet 4 and mounts the hold-down sheet 4 to an arbitrary positioned by making the hold-down sheet 4 freely attachable and detachable.