The Mauritanian economy is predominantly pastoral, with mining and fishing increasing in importance. Mauritania depends heavily on foreign aid. In 1999 the gross domestic product, which measures the total value of goods and services produced in the country, was $957,893,030, or $370 per inhabitant.

In the Sahel region of Mauritania a traditional subsistence economy is maintained, composed of livestock raising, agriculture, crafts, and petty trading. In the Sahara region, however, a modern economy is developing, based on the exploitation of iron-ore and copper resources and of the ichthyologically-rich continental shelf; the modern economy receives much needed capital investment and technical assistance from abroad. More than three-quarters of the Mauritanian population still lives by traditional activities, among which livestock raising is the most important. In numbers, goats and sheep are the most important livestock, followed by cattle, camels, donkeys, and horses. Cattle are raised primarily in the southern region, whereas goats and sheep are dispersed as far north as the limits of the Sahara. Camels are raised mostly in the north and the centre, especially in the Adrar region. The growth of the Mauritanian economy slowed in the 1980s after a lengthy period of rapid expansion in the 1960s and '70s. Agriculture and fishing account for almost one-third of the gross national product, with the industrial sector, including mining, contributing about one-quarter, public administration about 15 percent, and the remaining sectors about 30 percent.

A majority of the population still depends on agriculture and livestock for a livelihood, even though most of the nomads and many subsistence farmers were forced into the cities by recurrent droughts in the 1970s and 1980s. Mauritania has extensive deposits of iron ore, which account for half of total exports. The decline in world demand for this ore, however, has led to cutbacks in production. The nation's coastal waters are among the richest fishing areas in the world, but overexploitation by foreigners threatens this key source of revenue. The country's first deepwater port opened near Nouakchott in 1986. In the past, drought and economic mismanagement have resulted in a buildup of foreign debt. In March 1999, the government signed an agreement with a joint World Bank-IMF mission on a $54 million enhanced structural adjustment facility (ESAF). Mauritania withdrew its membership in the Economic Community of West African States (ECOWAS) in 2000. Privatization and debt relief are in full swing, and the rate of economic growth appears to be accelerating, especially in the construction, telecommunication, and information sectors. Diamonds and petroleum are beginning to be explored and exploited.