4 May 2016 Last updated at 16:08 BST
The Spratly Islands are disputed territory claimed by several Asian countries.
China has been building artificial islands there, saying the structures are for civilian purposes, but neighbouring countries are concerned at their possible military use.
The footage shows runways, an air traffic control tower, hangers and extensive construction work.
Footage from Chinese TV of a performance by military folk singer Song Zuying reveals the extent of construction on Fiery Cross Reef, a reclaimed island in the South China Sea.