〈書序〉作者的問題，歷來眾說紛紜。顧頡剛根據「周公居攝稱王」的論述，質疑「今本」〈書序〉的成書時間；又質疑「百篇」《尚書》之說，與伏生《尚書》「全經」之說衝突。導致顧頡剛對於〈書序〉作者的見解，迥異於前人。本文從〈書序辨序〉、顧頡剛的讀書筆記、日記等相關文獻，分析顧頡剛對於〈書序〉作者的質疑，並且說明顧頡剛對於〈書序〉作者的兩種論點。其一主張今本〈書序〉寫成於東漢，其次則推論百篇〈書序〉為張霸所為。顧頡剛的兩個論點，皆與張霸偽造《尚書》有關；本文從張霸偽造《尚書》的論述，審視顧頡剛對於〈書序〉作者推論的可能侷限。

There have been different opinions about the question of who wrote the preface to the Shangshu 尚書. Gu Jiegang 顧頡剛 was suspicious about the time of circulation of the preface, as well as about the view that the so-called “100 chapters” version of the Shangshu was originally orated by the Western Han Confucian Fu Sheng 伏生. Gu Jiegang's views about the Shangshu were different from those of previous scholars. This article analyzes Gu Jiegang's questioning of the authorship of the Shangshu preface, using his published work about the preface, as well as his notes, diary, and other relevant materials. It also lays out Gu's two positions concerning the authorship question. The first is that the preface was written in the Eastern Han and the second speculates that the preface to the “100 chapters” Shangshu was written by the Western Han scholar, Zhang Ba 張霸. Both of these arguments are connected to the notion that Zhang Ba fabricated the Shangshu. This article first elaborates on the issue of Zhang Ba's possible fabrication of the Shangshu and then discusses the limitations of Gu Jiegang's inferred logic concerning the authorship of the preface.