To provide a printing unit which attains an improvement of the reliability by suppressing an occurrence frequency of skipping of printing and paper jamming by controlling generation of skewing of a roll sheet at the time of setting of the roll sheet.

Even when the roll sheet 2 sent by a worker to between an insertion guide member 22 and a feed roller 24 skews, the feed roller 24 is rotated. When the roll sheet 2 is sent by some degrees to a printing part 20, a left side part of the roll sheet 2 hits a width guide member 23b. When the worker further rotates the feed roller 24 in this state, a feeding rate of the right side of the roll sheet 2 becomes larger than a feeding rate of the left side because of a resistance generated at a part where the width guide member 23b and the left side part of the roll sheet 2 hit each other at the left side of the roll sheet 2. The roll sheet 2 consequently rotates counterclockwise, so that the skew is corrected.