未央宮由一大片建築群構成，宮中設有嚴格管制出入的禁區，稱省中。本文根據人事活動來考察宮中建築設施的布局和功能，釐清分布於省中、省外的具體設施。進而發現，根據出入人員和設施功能的差異，宮中的政治空間實可分成內、中、外三層，卻與省中、省外的物理空間分隔不完全重疊，由此顯示政治空間隨著皇帝活動而變化的靈活性。 概略來說，未央宮以前殿為界，分成南北兩側。外層在未央宮南側，中層與內層略呈「回」字型，同在北側。外層包括前殿、宣室，與前殿以南的武臺、曲臺、高門、白虎諸殿，為皇帝舉行重大儀式、接見大臣、外賓與參加典禮的地方。此層全屬省外，公卿大臣可以進入。內層是後宮，屬於省中的內部，是皇帝的私人空間，有時皇帝也在這裡用閹人協助處理政務。 較特殊的是圍繞內層的中層，跨有省中和省外，又分成機能不同的南北二區。南區大抵是皇帝處理日常政務及商議機密政事的地方，包括：省中南緣的溫室殿，尚書與御史往往在省外鄰近省門處值勤；前殿西側的玉堂殿也在省外靠近省門處，黃門侍郎在此待命。北區包括：藏祕書處，如省中的天祿閣與省外的石渠閣；此外，皇帝召見文人學士多在此區省中的承明殿，而省外的承明廬、金馬門、宦者署則是文人學士待詔之處。

Weiyang Palace (未央宮 ) consisted of many building complexes. Among them, Inner Apartments refers to areas that were under strict access control. Based on administration records, this research looks at the spatial arrangement and functionality of the palace, and examines facilities that were located in the Inner Apartments and outside the Inner Apartments, respectively. According to the access control and different functionality of each facility, the political space of Weiyang Palace could be divided into three layers: the inner, the middle, and the outer. This distribution somehow differs from the physical space, as the physical space suggests a binary division of the palace into the Inner Apartments and the rest outside the Inner Apartments. This indicates that the political space is actually flexible and could be altered by emperors’ activities. Generally speaking, the Front Hall (前殿) is usually used to separate the palace into a south and a north part. The outer layer is in the south part; the middle and the inner layers are both in the north part, and the layout resembles the Chinese character 回. The outer layer includes various halls, such as Front Hall, Xuanshi (宣室), and south of Front Hall are Wutai (武臺), Qutai (曲臺), Gaomen (高門), and Baihu (白虎). These halls are for emperors to hold important rituals, meet ministers and ambassadors, and attend ceremonies. Also, this entire layer belongs to the area outside the Inner Apartments, and access was usually granted to ministers. On the other hand, the inner layer is what we consider as “imperial harem” and lies inside the Inner Apartments. It is emperor’s personal space, but sometimes the emperor would work on government affairs with the help of eunuchs in this space, too. What is more unique is the middle layer that surrounds the inner layer: it extends into both the Inner Apartments and the place outside the Inner Apartments. First, the middle layer could also be divided into a south and a north part based on different functions, and each part is composed by various facilities as well. Featuring Wenshi Hall (溫室殿 ) and Yutang Hall (玉堂殿 ), the south part is mainly the place where emperors would work on government affairs and engage in confidential conversations. Wenshi Hall lies at the south of the Inner Apartments, and the Imperial Secretariat and Attending Secretaries usually would assume their duties outside the Inner Apartments but near the apartment gate. Similarly, Gentleman of the Yellow Gate would await their orders outside the Inner Apartments but near the apartment gate at Yutang Hall, west of Front Hall. Meanwhile, the north part includes the Palace Private Library, which is consisted of Tianlu Pavilion (天祿閣) that lies in the Inner Apartments and Shiqu Pavilion (石渠閣) outside the Inner Apartments. The north part also includes Chengming Hall (承明殿), a place emperors would meet scholars and intellectuals and lies inside the Inner Apartments. At the same time, the north part includes facilities outside the Inner Apartments where the scholars and intellectuals would await for the emperor’s summons, such as Chengming Dorm (承明廬), Jinma Gate (金馬門 ), and Huanzhe Office (宦者署).