The total population of São Tomé and Príncipe was around at 165,034 in 2001. The capital and principal port is São Tomé located on the northeastern coast of São Tomé island. The population, descendants of peoples who came to the islands beginning in the late 1400s, is composed of six identifiable groups: mestiço, or mixed-blood; angolares, descendants of Angolan slaves; forros, descendants of freed slaves; serviçais, contract laborers from nearby African countries; tongas, children of serviçais born on the islands; and Europeans, mostly from Portugal. Portuguese is the official language, but 90 % of the people speak Fang, a Bantu language. Most of the people are Christian; 83% are Roman Catholic.

Of Sao Tome and Principe's total population, about 137,500 live on Sao Tome and 6,000 on Principe. All are descended from various ethnic groups that have migrated to the islands since 1485. 6 groups are identifiable: Mestico, or mixed-blood, descendants of African slaves brought to the islands during the early years of settlement from Benin, Gabon, and Congo -these people also are known as filhos da terra or "sons of the land"; Angolares, reputedly descendants of Angolan slaves who survived a 1540 shipwreck and now earn their livelihood fishing; Forros, descendants of freed slaves when slavery was abolished; Servicais, contract laborers from Angola, Mozambique, and Cape Verde, living temporarily on the islands; Tongas, children of servicais born on the islands; and Europeans, primarily Portuguese. In the 1970s, there were two remarkable population movements--the exodus of most of the 4,000 Portuguese residents and the influx of several hundred Sao Tomean refugees from Angola. The islanders have been absorbed largely into a common Luso-African culture. Almost all belong to the Roman Catholic, Evangelical Protestant, or Seventh-day Adventist Churches, which in turn retain close ties with churches in Portugal.