China gain control over all the Paracel Islands after a military engagement between the naval forces of the People's Republic of China and Republic of Vietnam (South Vietnam)

The Battle of the Paracel Islands (Chinese: , Pinyin: Xisha HaizhanVietnamese: Hi chin Hong Sa) was a military engagement between the naval forces of China and South Vietnam in the Paracel Islands on January 19, 1974. The battle was an attempt by the South Vietnamese navy to expel the Chinese navy from the vicinity. The confrontation took place towards the end of the Vietnam War.

As a result of the battle, the PRC established de facto control over the Paracels.

The Paracel Islands, also known as the Xisha Islands (simplified Chinese: 西沙群岛; traditional Chinese: 西沙群島; pinyin: xīshā qúndǎo; lit. 'West Sand Archipelago') and the Hoang Sa Archipelago (Vietnamese: Quần đảo Hoàng Sa, lit. 'Yellow Sand Archipelago'), are a disputed archipelago in the South China Sea.

The archipelago includes about 130 small coral islands and reefs, most grouped into the northeast Amphitrite Group or the western Crescent Group. They are distributed over a maritime area of around 15,000 square kilometers (5,800 sq mi), with a land area of approximately 7.75 square kilometers (2.99 sq mi). The name Paracel is of Portuguese origin, and appears on 16th-century Portuguese maps. The archipelago is approximately equidistant from the coastlines of the People's Republic of China (PRC) and Vietnam; and approximately one-third of the way from central Vietnam to the northern Philippines. The archipelago includes Dragon Hole, the deepest underwater sinkhole in the world. Turtles and seabirds are native to the islands, which have a hot and humid climate, abundant rainfall and frequent typhoons. The archipelago is surrounded by productive fishing grounds and a seabed with potential, but as yet unexplored, oil and gas reserves.

The colonial government of French Indochina set up telecommunication and weather stations on Pattle Island in the Crescent Group and Woody Island (South China Sea) ('Boisée' in French) in the Amphitrite Group in the 1930s, which they regularly supplied until 1945. Later, French and Vietnamese forces landed on Pattle Island in the Crescent Group in January 1947. By 1955 South Vietnam had taken possession of the Crescent Group. This situation changed with the Battle of the Paracel Islands in January 1974 when the PRC expelled the South Vietnamese from the Paracel Islands. South Vietnam's claim to the islands was inherited by the Socialist Republic of Vietnam which has ruled all of Vietnam since 1975.The ownership of the islands remains hotly contested. China, Vietnam, and Taiwan all claim de jure sovereignty, although the PRC has de facto control of the islands. In July 2012, China (PRC) declared a city named Sansha, under Hainan Province, as administering the area. In February 2017, the Asia Maritime Transparency Initiative reported 20 outposts of the PRC built on reclaimed land in the Paracels, three of which have small harbors capable of berthing naval and commercial ships.