PURPOSE: To facilitate centering of paper in paper feed direction by operating the width of sentence to be printed on a paper set in a carrying path and con trolling a carrying means to return the paper by half of thus operated width along the carrying path before starting the printing operation.

CONSTITUTION: When print mode is set through an input unit 21, a processing unit 22 decides whether a centering print mode is set for vertical character or not. When the answer is YES, a decision is made whether a document to be printed contains a single line or a plurality of lines and the widths in the paper feed direction are operated for respective cases. Half of thus operated width is then set as a paper return amount and the paper is returned by thus set amount after the paper is aligned with a print head in the center in paper feed direction. When the vertical character is printed from the starting position, it is printed while being centered in paper feed direction with reference to the central position of the vertical character in paper feed direction.