one of the largest of the Muslim cultural-linguistic groups of the Philippines. Numbering about 500,000 in the late 20th century, they live in the Sulu Archipelago southwest of Mindanao, mainly in the Jolo island cluster.

Like the other Filipino Muslims, the Tau Sug differ markedly from the Christians, who make up the overwhelming majority of the country's population. Land is owned by the clan and controlled by local leaders known as datus. The customs of marriage and the family are Islāmic. Kinship solidarity is very strong among the Tau Sug, and married children often live in the same household with the parents of the husband or near them.

The languages of all the Muslim groups are closely related to those of the central Philippines, which belong to the Austronesian (Malayo-Polynesian) family of languages.

Their economy is based upon rice farming. Fishing, trading by sea, and various handicrafts are also pursued.