Pratas Island, also known as the Tungsha Islands or the Dongsha Islands (Chinese: 東沙群島; pinyin: Dōngshā Qúndǎo; Pe̍h-ōe-jī: Tang-soa Kûn-tó; lit. 'East Sand Islands'), is a coral island situated in the northern part of the South China Sea administered as part of Cijin District, Kaohsiung, Taiwan. It is located about 170 nautical miles (310 km; 200 mi) southeast of Hong Kong. It has an area of about 240 hectares (590 acres), including 64 hectares (160 acres) of lagoon, and is the largest of the South China Sea Islands. It is the location of the Dongsha Airport.

There are three undersea features in the waters associated with Pratas Island: Pratas Atoll, North Vereker Bank and South Vereker Bank. The atoll is circular, and the crescent-shaped Pratas Island occupies its western part. Below the ocean's surface to the northwest (21°N 116°E / 21°N 116°E / 21; 116) of Pratas Island, North Vereker Bank rises to 11 metres (36 ft) below sea level and South Vereker Bank to 58 metres (190 ft) below sea level.

There are numerous oil wells to the west of the banks. In 2007, the Dongsha Atoll National Park was established on the island. The People's Republic of China claims the island, atoll and banks as part of Guangdong Province.

The English name of the island derives from the Portuguese Ilhas das Pratas ("Silver Plate Islands"), which was given to the atoll in the 16th century owing to its round shape.^{[citation needed]} Pratas Atoll is also called Pratas Reef.

Tungsha Island (Tung-sha Tao) (Chinese: 東沙島; pinyin: Dōngshā Dǎo; Wade–Giles: Tung¹-sha¹ Tao³; Pe̍h-ōe-jī: Tang-soa-tó) is the Wade–Giles-derived romanization of the Mandarin Chinese name for the island, and Dongsha Island (Dongsha Dao) is the pinyin-derived name. A smaller island with the same Chinese character name is located in the Taiwan-administered Dongyin Township in the Matsu Islands in the East China Sea.

The area including the island, atoll and banks is also called the Pratas Islands (Chinese: 東沙群島; pinyin: Dōngshā Qúndǎo; Pe̍h-ōe-jī: Tang-soa Kûn-tó; lit. 'East Sand Islands'), the Tungsha Islands and the Dongsha Islands. Despite these names, Pratas Island is the only island; there is no group of islands. Yoshiyuki Ogasawara [ja] in The Diplomat described the other entities as "essentially rocks".

On May 29, 1945, the American submarine USS Bluegill occupied the island after shelling Japanese positions there in January, raising an American flag, claiming it for the United States, and proclaiming it Bluegill Island. Giving the island a new name, and claiming it for the U.S., was done independently by the Submarine's commander without support from the United States government, although the landing was acknowledged by the Commander, Submarine Force, U.S. Pacific Fleet Merrill Comstock in his report to the Pentagon. The U.S. government took no effort to further pursue this and never formally claimed the island.

The East Indiaman Earl Talbot was wrecked on Pratas Island on or about 22 October 1800 with the loss of all aboard. At the time the island was known to British sailors as "Perates". In 1851, the British screw sloop HMS Reynard wrecked on the south-east bend of Pratas Atoll while going to the aid of another wrecked vessel; the crew were all saved. Decades later, the boilers and parts of the machinery of the wreckage of HMS Reynard remained visible on the atoll.