A magnetic printing apparatus provides a recording head having a plurality of channels with different tracking widths. A locus is described by a preceding channel having a wide tracking width, another locus is described being partly overlapped on said locus by using a succeeding channel having a narrow tracking width. The width of locus described by the preceding channel is so corrected as will become nearly equal to the tracking width of the succeeding channel, while the overlapped portion of said locus is written into the succeeding channel.