Surigao del Sur (Surigaonon/Tandaganon: Probinsya nan Surigao del Sur; Cebuano: Habagatang Surigao; Filipino: Timog Surigao) is a province in the Philippines located in the Caraga region in Mindanao. Its capital is Tandag City. Surigao del Sur is situated at the eastern coast of Mindanao and faces the Philippine Sea to the east.

Before the arrival of the Spanish in the 16th century, the aborigines of the province were the Mamanua and Manobo. Austronesian people from the Visayas came to settle with the natives. It was with the arrival of the immigrants that the province acquired its name from one of the natives, Saliagao who are now known as Surigaonon, who lived near the mouth of the river. The name Saliagao was later pronounced Surigao by the inhabitants.

Another version of the origin of the name "Surigao" is that, Visayan fishermen forced by the strong current of the Surigao Strait, sought refuge in one of the huts somewhere in the province. The Mamanua who thought that these fishermen wanted to occupy the hut by force said "Agaw", the term which was later given a prefix "Suri".

Surigao extended from what is known as Agusan, including the islands east of it and the northern regions of Davao and the capital of the province that time was Caraga and so the Spaniards called the people Caragas.

The aborigines of Surigao del Sur were a mixture of different races which include the Mandaya, Mamanua, Mansaka and Manobo. These groups were of Malayan-Indonesian ancestry who immigrated thousands of years ago. In the course of their migration, these primitive nomads were believed to have separated their ways in some portions of the archipelago in search for food (i.e., during the of the glacial ages). It was believed further that they first settled in the northern island of the country who later took their bancas and reach the shores of Mindanao particularly in the Provinces of Surigao and Davao. They scattered among themselves in spots either in pairs or by family clans, retaining their own customs, dialects and ways of life.

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