書序之體，肇白先秦，追及兩漢，發展益備，其中司馬遷《史記‧太史公自序》具有承先啟後的重要地位。本文以司馬遷〈太史公自序〉體制之分析為基點出發，再透過對其他現存的漢代書序（以作者為其自撰之書所作的書序為主）的歸納整理，從而發現漢代作者自著書之書序，基本上皆大致體現了某些共同的體制與特色，其中包括：一、敘述作者家世先祖及其生平事蹟；二、闡述全書旨意和敘述著作該書的宗旨、動機；三、條其篇目，並撮述各篇之要旨；四、置於全書之末。除第四項是屬於外部的篇籍形式之外，其他三項皆關聯到書序本身的內在功能與要求。本文除討論這些體制的內涵、性質與功能之外，也嘗試解釋導致漢代書序「體制化」的原因與動力。 The book preface emerged as a literary form in the pre-Ch'in period and developed considerably in the Han dynasty. In the course of this development, Ssu-ma Ch'ien's Preface to the Shih Chi played a pivotal role as heir to the early tradition and a paradigm for later writers. The starting point of this paper is an analysis of the structure of Ssu-ma Ch'ien's Preface. Through an examination of this and other extant Han dynasty prefaces (focusing on prefaces by the authors of the works themselves), this study discovers that prefaces by Han dynasty authors all tend to share a certain common structure and features. These inc1ude: (1) a description of the writer's ancestry and major events in his life; (2) a description of the main themes of the book and a statement of the aims of the work and motivation for writing it; (3) a list of the contents of the work, including the main point of each chapter; and (4) placement of the preface at the end of the work. Aside from the fourth point, which pertains to external, editorial form, the other three points all relate to the function and requirements of the preface. In addition to discussing the content, character, and function of this common structure, this paper attempts to explain the reasons that led to the structural standardization of Han dynasty prefaces.