Gasherbrum II (Urdu: گاشر برم -2; simplified Chinese: 加舒尔布鲁木II峰; traditional Chinese: 加舒爾布魯木II峰; pinyin: Jiāshūěrbùlǔmù II Fēng), also known as K4, is the 13th highest mountain on Earth, located on the border of Gilgit-Baltistan province, Pakistan and Xinjiang, China. At 8,035 metres (26,362 ft), Gasherbrum II is the third highest peak of the Gasherbrum massif, located in the Karakoram range of the Himalaya.

The standard climbing route is via the southwest ridge as it is relatively free of objective hazards such as ice falls and avalanches. A typical expedition lasts 7 to 8 weeks with climbing permits costing about US$7,500 for five climbers.

Gasherbrum II was first climbed on July 7, 1956 by Fritz Moravec, Josef Larch and Hans Willenpart of an Austrian expedition.