Baishiya Karst Cave (Chinese: 白石崖溶洞) is a high-altitude paleoanthropological site and a Tibetan Buddhist sanctuary located on the northeastern edge of the Tibetan Plateau in Xiahe County, Gansu, China. This karst cave is the site of the discovery of the earliest hominin fossil found on the Tibetan Plateau, the Xiahe mandible. The mandible, by way of palaeoproteomic analysis, is the first confirmed discovery of a Denisovan fossil outside of Denisova Cave. This fossil discovery shows that archaic hominins were present in a high-altitude, low-oxygen environment by around 160,000 years ago.