Niú Sēngrú 牛僧孺 (780–848 or 849; zì Sīàn 思黯; ennobled as Qízhāngjùngōng 奇章郡公, hence often called Niú Qízhāng 牛奇章), of Āndìng 安定 (modern Gānsù), was one of the leading statesmen and xiǎoshuō writers of the mid-Táng. His standard biography is Jiù Táng shū 172.4469-73; CBDB id 32054. He passed the jìnshì in Yuánhé 元和 3 (808) and rose through a series of provincial and ministerial offices to Zǎixiàng (chief minister) under both Jìngzōng 敬宗 (824–826) and Wénzōng 文宗 (826–840), and to Tàizǐ shàoshī 太子少師 under Wǔzōng 武宗. He is the principal figure of the Niú faction in the protracted NiúLǐ 牛李 factional dispute (Lǐ being 李德裕 Lǐ Déyù), the dominant political quarrel of the Mùzōng — Wǔzōng period. Demoted late under Wǔzōng, he was rehabilitated under Xuānzōng 宣宗 and died in 848 (some sources 849).
As a xiǎoshuō writer, Niú Sēngrú is the author of the Xuánguài lù 玄怪錄 (KR3l0095) — the great mid-Táng zhìguài and chuánqí anthology in 10 juàn, which inaugurated the late-Táng tradition of fully-developed chuánqí fiction as a genre distinct from earlier zhìguài. His Xuánguài lù influenced his successor Lǐ Fùyán’s 李復言 Xù xuánguài lù 續玄怪錄 (KR3l0096) and, through his maternal grandson 張讀 Zhāng Dú, the Xuānshì zhì 宣室志 (KR3l0110) — making the Niú-line family-literary tradition the principal source of Táng anomaly-anthology writing across three generations. He is also noted in late-Táng sources as a major patron of Chán 禪 Buddhist monasteries (notably the Tiāntāi shān 天台山 establishments) and of Mao-shan 茅山 Daoism. Wilkinson §62 cites him as a foundational figure of the Táng chuánqí / biji line.