A moisture removal apparatus and method of an image read-out apparatus, in which the image read-out apparatus includes a contact image sensor (CIS) provided with a document glass on which a document is put on an upper portion thereof and a read-out unit to read out an image of the document, and a pressing roller rotatably provided in contact with a top surface of the CIS to press and transfer the document. The moisture removal apparatus includes a heater to heat the document glass at a predetermined temperature to remove moisture, a power source to apply a predetermined voltage to the heater, a sensing unit to provide basic information to determine driving conditions of the heater, and a controller to control heating conditions of the heater on the basis of the information received from the sensing unit. Thereby, the moisture on the top surface of the document glass may be effectively removed.