North or Bei Hulsan Lake, also known by other names, is a lake northeast of Golmud in Dulan County, Haixi Prefecture, Qinghai Province, China. A part of the Qarhan Playa, it is filled from the east by the Qaidam River. Like the other lakes of the surrounding Qaidam Basin, it is extremely saline.

Hulsan or Hollusun Nor is a romanization of the Mongolian name meaning "Reed Lake", from their former abundance in the area. The adjective "north" distinguishes it from nearby South Hulsan Lake. Huoluxun and Huobuxun are the pinyin romanizations of the Mandarin pronunciation of the same name's transcriptions into Chinese characters. Bei Hulsan or Beihuobuxun is the same name, prefixed with the Chinese word for "North".

North Hulsan Lake lies in the northern Hulsan subbasin at the eastern edge of the Qarhan Playa in the southeastern corner of the Qaidam Basin at an elevation of 2,675 m (8,780 ft). It lies east of Xiezuo Lake and north of South Hulsan Lake. It was reported by Zheng in 1997 as usually about 90.4 km (35 sq mi), and by Zhang & al. in 2014 as 82.49 km (32 sq mi), but by Zhou & al. as varying between dry and wet years from 52.55–88.21 km (20–34 sq mi). North Hulsan Lake is chiefly fed from the east by the Qaidam River (t 柴達木河, s 柴达木河, Cháidámù Hé). In the area's hyperarid climate, there is generally only 28–40 mm (1–2 in) of annual rainfall but about 3,000 mm (120 in) of annual evaporation. It is never more than about 1 m (3 ft 3 in) deep. An inflow from the north by mineral springs in the playa's northern karst zone contribute a smaller volume of water but its much higher solute concentration greatly affects the lake and its sediments. North Hulsan Lake's sediments have a relatively higher potassium content than most other lakes in the playa.

North Hulsan Lake has been greatly affected by the rapid expansion of the industrial processing of Qarhan's salt lakes for potassium and other valuable minerals since 2000. Fang & al. found it had lost 8.1 Gt (8.9 billion short tons) of water between 1995 and 2015, and Zhou & al. reported that the lake proper could not be distinguished at all from the surrounding salt pans in satellite imagery as of 2014.

• Qarhan Playa and Qaidam Basin
• List of lakes and saltwater lakes of China

• Du Yongsheng; et al. (April 2018), "Evalutation of Boron Isotopes in Halite as an Indicator of the Salinity of Qarhan Paleolake Water in the Eastern Qaidam Basin, Western China", Geoscience Frontiers, vol. 10, Beijing: China University of Geosciences, pp. 1–10, doi:10.1016/j.gsf.2018.02.016.
• Fang Yu; et al. (June 2019), "Assessment of Water Storage Change in China's Lakes and Reservoirs over the Last Three Decades", Remote Sensing, vol. 11, doi:10.3390/rs11121467.
• Garrett, Donald Everett (1996), Potash: Deposits, Processing, Properties, and Uses, London: Chapman & Hall, ISBN 9789400915459.
• Gross, Alexander (1935), "China and Adjacent States", Geographia Atlas of the World, New York: Geographia Map Co.
• Jia Xiru (20 February 2019), "Qīnghǎi Měnggǔyǔ Dìmíng de Jǐge Tèsè 青海蒙古語地名的幾個特色 [Several Characteristics of Mongolian Placenames in Qinghai]", Xuěhuā Xīnwén 雪花新闻 [Snowflake News] (in Chinese).
• Lowenstein, Timothy K.; et al. (2009), "Closed Basin Brine Evolution and the Influence of Ca–Cl Inflow Waters: Death Valley and Bristol Dry Lake, California, Qaidam Basin, China, and Salar de Atacama, Chile", Aquatic Geochemistry, vol. 15, Springer, pp. 71–94, doi:10.1007/s10498-008-9046-z, S2CID 129168176.
• Spencer, Ronald James; et al. (1990), "Origin of Potash Salts and Brines in the Qaidam Basin, China" (PDF), Fluid-Mineral Interactions: A Tribute to H.P. Eugster, Special Publication No. 2, Geochemical Society.
• Yu Ge; et al. (2001), Lake Status Records from China: Data Base Documentation (PDF), MPI-BGC Tech Rep, No. 4, Jena: Max Planck Institute for Biogeochemistry.
• Zhang Guoqing; et al. (27 July 2014), "Estimating Surface Temperature Changes of Lakes in the Tibetan Plateau using MODIS LST Data", JGR Atmospheres, vol. 119, American Geophysical Union, pp. 8552–8567, doi:10.1002/2014JD021615, S2CID 128890467.
• Zheng Mianping (1997), An Introduction to Saline Lakes on the Qinghai–Tibet Plateau, Dordrecht: Kluwer Academic Publishers, ISBN 9789401154581.
• Zhou Shilun; et al. (2016), "Spatial-Temporal Variations and Their Dynamics of the Saline Lakes in the Qaidam Basin over the Past 40 Years", Earth and Environmental Science, IOP Conference Series, vol. 46, Bristol: IOP Publishing, doi:10.1088/1755-1315/46/1/012043.