<p>While archival buildings are often treated implicitly as neutral containers of records, this article argues that they are themselves archives—tangible, readable records of historical, political, and cultural information. Through horizontal comparison of typical archival buildings across geography, time, hierarchy, and theme, combined with vertical material culture analysis of Huangshicheng (China’s Imperial Archives, 1534-present), this study demonstrates that archival buildings record information through their complete material systems: architectural body, interior spaces, archival facilities, and environmental atmosphere. The article introduces the concept of “design writing” to theorize how design functions as a recording mechanism in archival buildings. Parallel to traditional archival writing (inscription on paper, bamboo, or parchment), design writing encodes information through material selection, spatial organization, color application, and decorative patterns. However, design writing exhibits distinctive characteristics: multi-sensory perception, embedded power distribution, and dynamic accumulation across time. Crucially, it records both intentional and unintentional information, providing multi-dimensional historical evidence that can corroborate or complicate traditional archival records. By expanding the definition of the term archive and revealing design’s mediating role in historical recording, this research contributes new theoretical perspectives to archival studies.</p>