No. 42 Squadron was a Royal Australian Air Force (RAAF) mine laying and maritime patrol squadron of World War II formed in June 1944. It conducted patrol and mine-laying operations over the Netherlands East Indies (NEI) from August 1944 until the war ended a year later. It also conducted operations in the waters off southern China in early 1945. Following the Japanese surrender, the squadron performed transport and reconnaissance flights until it was disbanded in November 1945.