The Southern Theater Command Navy (STCN), or the South Sea Fleet (SSF) until 2018,[1] is a formation of China's People's Liberation Army Navy (PLAN) and the naval component of the Southern Theater Command.

[3] The Riverine Defense Command commanded the Wanshan Archipelago Campaign in May to August 1950[4] and was the "nucleus" of the South Central China Military Region Navy created by the Fourth Field Army in December 1950.

The military region's navy became the PLAN's South Sea Fleet in 1955.

[5] The SSF won the Battle of the Paracel Islands against South Vietnam in 1974.

[10] It controls coastal defenses west from to Dongshan County and in the South China Sea.