A device for supplying and rewinding an object to be printed for digital printing comprising: a supply roll on which the object to be printed is wound; a first transfer roll which transfers the object to be printed being supplied from the supply roll to a lower side of a head unit; a second transfer roll which discharges the object printed with an image by the head unit; and a rewinding roll which has a rotation axis parallel to a rotation axis of the supply roll, and is rotated by a rewinding drive means so as to rewind and collect the object printed with an image being discharged from the second transfer roll, wherein one end of the object to be printed is unwound and supplied from the supply roll, passed through an upper side of the first transfer roll and the second transfer roll, and fixed to the rewinding roll, a first and a second auxiliary roll; characterized in that the device comprises: a first guide is disposed between the supply roll and the first transfer roll, and a second guide is disposed between the second transfer roll and the rewinding roll; in that the first auxiliary roll is movably installed in the first guide and configured to, after passing the object to be printed through the first and second transfer rolls and fixing to the rewinding roll, come close and press the object to be printed loosely positioned between the supply roll and the first transfer roll so as to increase a contact area of the object be printed with the first transfer roll; and in that the second auxiliary roll is movably installed in the second guide and configured to, after passing the object to be printed through the first and second transfer rolls and fixing to the rewinding roll, come close and press the object to be printed loosely positioned between the second transfer roll and the rewinding roll so as to increase the contact area of the object be printed with the second transfer roll. a supply roll on which the object to be printed is wound; a first transfer roll which transfers the object to be printed being supplied from the supply roll to a lower side of a head unit; a second transfer roll which discharges the object printed with an image by the head unit; and a rewinding roll which has a rotation axis parallel to a rotation axis of the supply roll, and is rotated by a rewinding drive means so as to rewind and collect the object printed with an image being discharged from the second transfer roll, wherein one end of the object to be printed is unwound and supplied from the supply roll, passed through an upper side of the first transfer roll and the second transfer roll, and fixed to the rewinding roll, a first and a second auxiliary roll; characterized in that the device comprises: a first guide is disposed between the supply roll and the first transfer roll, and a second guide is disposed between the second transfer roll and the rewinding roll; in that the first auxiliary roll is movably installed in the first guide and configured to, after passing the object to be printed through the first and second transfer rolls and fixing to the rewinding roll, come close and press the object to be printed loosely positioned between the supply roll and the first transfer roll so as to increase a contact area of the object be printed with the first transfer roll; and in that the second auxiliary roll is movably installed in the second guide and configured to, after passing the object to be printed through the first and second transfer rolls and fixing to the rewinding roll, come close and press the object to be printed loosely positioned between the second transfer roll and the rewinding roll so as to increase the contact area of the object be printed with the second transfer roll. a first guide is disposed between the supply roll and the first transfer roll, and a second guide is disposed between the second transfer roll and the rewinding roll; in that the first auxiliary roll is movably installed in the first guide and configured to, after passing the object to be printed through the first and second transfer rolls and fixing to the rewinding roll, come close and press the object to be printed loosely positioned between the supply roll and the first transfer roll so as to increase a contact area of the object be printed with the first transfer roll; and in that the second auxiliary roll is movably installed in the second guide and configured to, after passing the object to be printed through the first and second transfer rolls and fixing to the rewinding roll, come close and press the object to be printed loosely positioned between the second transfer roll and the rewinding roll so as to increase the contact area of the object be printed with the second transfer roll.