Mastung District is located in the northwest of Balochistan (Pakistan), covering an area of 3,308 km². It lies south of Quetta District, with elevations between 5,600 feet (1,700 m) to 10,000 feet (3,000 m) above sea level.

The Hazarganji-Chiltan National Park, one of Balochistan's protected areas, is situated between Quetta and Mastung, about 20 kilometres (12 mi) southwest of Quetta city.

Formerly a sub-division of Kalat District, Mastung was granted district status in July 1991 and has functioned independently since 18 February 1992. Its name is traditionally derived from the Brahui words Mas (mountain) and Tung (hole).

The district is prone to natural hazards, including earthquakes, floods, and droughts. Its varied landscapes encompass the high Sulaiman Mountains, desert, and forest habitats, and support a rich diversity of flora. Medicinal plants remain an important part of rural healthcare, while agriculture is the primary source of livelihood for nearly half the population, with major crops including wheat, barley, cumin, fodder, melon, potato, and other vegetables.

The district consists of following Tehsils:

Prior to 2006, the three tehsils contained 12 union councils: Khadkoocha, Ghulam Parenz, Karez Noth, Mastung-1, Mastung-2, Sorgaz, Tehsil Dasht, Isplinji, Kanak, Shaikh Wasil, Kardigap and Soro. In 2006, one additional union council formed with the name of Alizai, making the total union councils to 13.

As of the 2023 census, Mastung district has 43,695 households and a population of 313,271. The district has a sex ratio of 113.70 males to 100 females and a literacy rate of 45.97%: 57.26% for males and 33.27% for females. 109,539 (35.07% of the surveyed population) are under 10 years of age. 40,374 (12.89%) live in urban areas. 1,696 (0.54% of the surveyed population) was from religious minorities, of which 900 were Hindus and 750 Christians.

At the time of the 2023 census, 89.05% of the population spoke Brahui, 7.19% Balochi and 2.12% Pashto as their first language.