During the assault of the Japanese in February 1942, Changi was targeted as one of the first attack points. In a day or two, it was occupied by the Japanese army moving from Puala Ubin. Soon after that OCH was converted to a military hospital where all the wounded soldiers and civilians were attended to. After the Japanese Occupation ended, it was converted to a public hospital and later with a Military ward on the third level.

From February 1997 onwards, OCH was closed and replaced by the new Changi General Hospital. It got isolated and left vacant there since then. Everything there is now dark and quiet.