The Northwestern thorn scrub forests are a xeric shrubland ecoregion of Pakistan and northwestern India, stretching along the border lowlands and hills between the two countries. Once covered in deciduous forest, this ecoregion has been degraded through agriculture and the extraction of timber so that it currently has a scanty covering of thorny scrub dominated by such trees as Acacia senegal, Acacia leucophloea and Prosopis cineraria. Where the soils are particularly saline, there are patches of semi-desert. A number of mammals are found in this habitat and about four hundred species of bird. Some small areas are protected but the collection of firewood and the conversion of the land to subsistence farming continues.
The ecoregion encircles the Thar Desert and Indus Valley Desert ecoregions. It stretches along the border lowlands and hills between India and Pakistan and includes: the western half of Gujarat (excluding the mountain of Girnar), and extending through Rajasthan, where it is bounded on the southeast by the Aravalli Range; most of Haryana and Punjab states of India as well as the Jammu region of Jammu and Kashmir, extending to the foothills of the Himalayas; in Pakistan, most of Punjab province, extending into easternmost Northwest Frontier and Baluchistan provinces and western Sindh.
This ecoregion, together with the Thar Desert and Indus Valley Desert ecoregions, form Miklos Udvardy's "Thar Desert" Biogeographic province.