Bayanbulak Grassland National Nature Reserve () (from Mongolian abundant spring) is the second largest grassland in China, located in the Bayanbulak Basin of the Tian Shan mountains in northwest China. The terrain is mostly flat, and encompasses a middle section of the Kaidu River (Peacock River). The reserve is 200 km northwest of Korla in the Bayingolin Mongol Autonomous Prefecture of Xinjiang Uyghur Autonomous Region.