To make it possible to easily elucidate the cause for erroneous sorting when postal items are erroneously sorted.

This sorting apparatus subjects character recognition data 42 used for sorting of the postal items after video coding, video coding sorting destinations 43, operators' IDs 44 and image data 41 of the postal items to erroneous sorting analysis, then to displaying or image printing and compares the image data 41 and the video coding sorting destinations 43. As a result, the analysis of the cause for the erroneous sorting may be facilitated.