本研究從簡牘物質形態的角度討論漢代基層公文書制度，及其反映的行政程序，特別聚焦於「兩行」的制度地位。首先以深具研究傳統的西北漢簡為開端，探討「兩行」與「札」等形制與文書性質的關係，分析它們在文書行政過程中扮演的角色，試圖勾勒正本、副本、草稿與檔案等不同文書性質之間的界線，並且關注文書性質如何隨著不同行政階段而轉變。在漢代公文書制度中，「兩行」具有特殊地位，基本作為寄發的正本與相應的留存副本使用，且在外觀上與其他性質的文書作出區隔，這種視覺差異有助於官吏在行政過程中快速分辨不同類型的文件。接著以漢代甲渠候官遺址為例，更細緻地甄別遺址現象與簡牘出土地點，闡明不同性質文書於不同空間中的意義。特別觀察「兩行」在遺址內、外的分布情況，進而重新考慮官署內部職能分工與文書移動流向。「兩行」文書的性質及制度地位，更有助於我們推測與解釋遺址空間的性質與相應的行政程序。

This article purports to discuss the official document systems and administration at the basic level employed during the Han dynasty in view the material nature and writing features of bamboo and wooden manuscripts, with a focus on the liang hang (兩行). The principal data for the study were original manuscripts as well as information about Han dynasty sites in northwest China, in particular. This article presents an analysis the relationship between document form and content in the document classifications of liang hang and zha (札), and their respective roles in administration procedure, such as original version, copy, draft and archive. Special attention is paid to how the nature of the documents changed during the different administrative stages. The research found that liang hang documents were treated as original versions and preserved copies and therefore had a special status in the official document system during the Han dynasty. The appearance of liang hang documents differs distinctly from that of other forms; it thus helped officials to distinguish between documents in administrative procedures. Moreover, the nature and status of liang hang documents also contribute to our speculations and interpretation of the nature of the physical site space and corresponding administrative procedures.