Lhünzhub County, also called Lhundrub or Linzhou County, is a county in Lhasa prefecture-level city towards the north-east of the main center of Lhasa, Tibet, China. It covers an area of 4,512 km² (1,742 sq mi) and as of 2000 had a population of 50,895 people, almost all classified as rural. The southern portion, the Pengbo River Valley, contains fertile arable land, while the colder and more mountainous northern portion primarily supports grazing.