Princess Der Ling (traditional Chinese: 德齡公主; simplified Chinese: 德龄公主; pinyin: Délíng Gōngzhǔ), also known as Secret Files of the Qing Imperial Palace: Princess Der Ling (清宮秘檔之德齡公主; 清宫秘档之德龄公主; Qīnggōng Mìdàng zhī Délíng Gōngzhǔ), is a Chinese period drama television series based on the historical novel of the same name written by Xu Xiaobin.

The series premiered on CCTV-8 on 30 August 2006,[3] and had been broadcast on Top TV [zh] in Taiwan since 2009, with Taiwanese Hokkien dubbing.

[5] Upon their return to China from France, Der Ling (Zhang Jingjing) and Roung Ling (Sun Yifei), daughters of the Qing-dynasty diplomat Yu Keng [fr] (Liu Wenzhi), are installed as court ladies to the Empress Dowager Cixi (Lü Zhong).

The Yu sisters, with the feeling of reforming an ancient empire, eventually realise its impossibility of change, and witness the dynasty's gradual demise.

According to the Peking University professor Chen Xiaoming, in Xu Xiaobin's novel, as well in the series adaptation, "Der Ling and Roung Ling are symbols of Western civilisation".