Yan An shu 嚴安書 "Book of Yan An", also called Yan An 嚴安, was a political treatise written by the Han-period 漢 (206 BCE-220 CE) official Yan An 嚴安. He hailed from Linzi 臨淄 (near modern Linbo 淄博, Shandong) and lived during the reign of Emperor Wu 漢武帝 (r. 141-87 BCE). About his life it is only known that he was granted the title of gentleman of the interior (langzhong 郎中) because of his book, and was later promoted to commandant of cavalry (jima ling 騎馬令).
The imperial bibliography Yiwen zhi 藝文志 in the official dynastic history Hanshu 漢書 lists a book called Zhuang An 莊安 among the coalition advisors (zonghengjia 縱橫家). The name Zhuang 莊 was his actual family name but was avoided during the Later Han period 後漢 (25-220 CE) because it was the personal name of Emperor Ming 漢明帝 (r. 57-75 CE; Liu Zhuang 劉莊), and was replaced with Yan 嚴.
The Qing-period 清 (1644-1911) scholar Ma Guohan 馬國翰 (1794-1857) collected the surviving fragments of the book Yan An shu and united them in one chapter with fragments of the book Xu Le shu 徐樂書. These are to be found in Ma's series Yuhan shanfang jiyi shu 玉函山房輯佚書.
The political statements of Yan An lay stress on the strengthening of the power of the central government and the emperor. Because the local governors were too strong, the emperor had to pacify the inner court and to appease the regions of the empire (jing nei an wai 靜內安外).