Through textual research on the Song Dynasty block-printed large-character and small-character editions of Shang han lun (Treatise on Cold Pathogenic Disease), it can be definitely verified that Yang Shoujing's so-called 'facsimile handwritten copy of Northern Song edition' was an apocrypha fabricated by Yang himself. Japanese Horikawa's An zheng edition, the original edition adopted by Yun Tieqiao's photocopy, did exert a profound and lasting influence on China. After collating the Song Dynasty block-printed edition collected in Japan National Cabinet Library with the one collected in the National Beijing Library thoroughly, and checking the prefaces and postscripts carefully, it has been found, for the first time, that these two editions, both called 'Song edition', differ dramatically.