Niu Xianke (牛仙客) (675 – September 2, 742), formally Duke Zhenjian of Bin (豳貞簡公), was a general and official of the Tang Dynasty. He served as a chancellor during the reign of Emperor Xuanzong of Tang. He took an unconventional path to the position of chancellor by starting as a low-level bureaucrat and gradually getting promoted, rather than going through the imperial examinations, and was known for being careful and obedient to fellow chancellor Li Linfu.