Lhoka Prefecture ( "south of the mountains"), also known as Shannan Prefecture ), is an administrative district in the southeastern Tibet Autonomous Region. Lhoka Prefecture includes Gonggar County within its jurisdiction with Gongkar Chö Monastery, Gonggar Dzong, and Gonggar Airport all located near Gonggar town.
Located on the middle and lower reaches of the Yarlung Valley, formed by the Yarlung Tsangpo River, Lhoka Prefecture is often regarded as the birthplace of Tibetan civilization. It is bounded by the prefectures of Lhasa to the north, Nyingchi to the east, Shigatse on the west and the international border with India and Bhutan on the south. The prefecture measures east to west and from north to south. Its uniqueness stems from the fact that Tibet's earliest agricultural farmland, its first palace and first Buddhist monastery are all located in Lhoka. It also has the distinction of having held the first lhamo performance. Tibetan people constitute 98% of the population, the remaining 2% being Han, Hui, Mönpa, Lhoba and other ethnic groups.
Lhoka Prefecture has 12 counties and its capital is Tsetang, which is located 183 kilometres from Lhasa. It covers an area of , which includes South Tibet, a disputed territory under the control of the Indian state of Arunachal Pradesh. Its topography averages above sea level. The population of Tsetang city was 330,100 as of 2007 with Tibetans accounting for 96% of the total population.
Lhoka Prefecture has not only an ancient historical background but is also the most prosperous in Tibet.